• write each answer in simplest form.
1. 1/6 +2/6
2. 2/5 - 1/5

Answers

Answer 1

Answer:

1. 1/2

2. 1/5

Step-by-step explanation:

I used a calculator!

Answer 2

Answer:

1.3/6 or 1/2

2.1/5

Step-by-step explanation:

Just write that out, thats all the steps there is, 3/6 simplifies to 1/2 because they're equivalent


Related Questions

Write the equation of the line that passes through the given point and is perpendicular to the given line.

(Only need 20 and 22)

Answers

Answer:

4x - 5y = 30

4x - 5(0) = 30

x1 = 7.5 y1 = 0

Find y-intercept

The y-intercept is where the graph crosses the y-axis. To find the y-intercept, we set x2=0 and then solve for y.

4x - 5y = 30

4(0) - 5y = 30

y2 = -6 x2 = 0

(x1,y1) and (x2,y2)

(7.5,0) and (0,-6)

Solve for x

To solve for x, we solve the equation so the variable x is by itself on the left side:

4x - 5y = 30

x = 1.25y + 7.5

Solve for y

To solve for y, we solve the equation so the variable y is by itself on the left side:

4x - 5y = 30

y = 0.8x - 6

there are 10 boys and 15 girls. The teacher chooses a student by random. Eric says that the probability for a boy to be chosen is 0.5. Jenny says he is wrong. Who is correct. Give reasons

Answers

In a case whereby there are 10 boys and 15 girls and the teacher chooses a student by random, then the probability that a boy will be chosen is 2/5 which means Jenny is right.

How can the probability be calculated?

Since there are  there are 10 boys and 15 girls, then the total number of the population will be (10+15)=25

Then the probability of that a boy will be chosen if one of them is been chosen at random will then be =10/25 = 2/5

Therefore, Jenny is very correct because the  probability of that a boy will be chosen if one of them is been chosen at random will then be 2/5.

Learn more about probability at:

https://brainly.com/question/24756209

#SPJ1

100 Points!!
Activity
A submarine is at a depth of 100 feet below sea level. Then it starts to dive at a rate of 50 feet per minute. Use this information to answer the following questions.

Question 1
Part A
For this situation, what is the independent variable (include units)?

Part B
What is the dependent variable (include units)?

Part C
What is the slope of the line that models this situation?

Part D
What is the y-intercept of the line that models this situation?

Question 2
Write the equation of the line that models the situation using the slope and y-intercept found in parts C and D of question 1.

Answers

Answer:

See below.

Step-by-step explanation:

The initial depth is 100 feet below sea level or 100 ft.

Diving rate is 50 feet per minute or 50 ft/min.

Question 1

Part A

The diving rate is the independent variable, which is:

50 ft/min

Part B

The depth at any point is the dependent variable, which is different after number of minutes, in ft.

Part C

The slope is the diving rate in this situation.

Part D

The initial depth is the y-intercept, the starting point.

Question 2

The equation of the line is:

y = mx + b, substituting the values,y = 50x + 100

Answer:

Independent variable: Time in minutes

Dependent variable: The elevation in feet

Slope: -50

Y-Intercept: -100

Step-by-step explanation:

Just did the assignment

Identify which graph can be used to solve each equation. Enter the letter of the correct graph next to the
equation.

Pleaseee help me

Answers

The first ones C
Second is A
Last is B

PLEASE HELP THIS IS DUE❗️❗️❗️❗️❗️

Answers

Answer:

Step-by-step explanation:x=-2x

The sum of twice a number and eight is 20. What is the number?

Answers

Answer:

6

Step-by-step explanation:

let the number be equal to x

The sum of twice a number= 2x

2x+8=202x=20-82x=122x/2=12/2x=6

Arrange the numbers 1 to 9 so that the sum of the three numbers in any straight line = 15​

Answers

Answer:

1     8    6

9    4    2

5    3    7

Step-by-step explanation:

1) When solving problems like this it is best to start with the smallest number. In this case the smallest number was 1, so that was placed in the top left corner.

2) The smallest number must be next to the two largest numbers so, 8 and 9 can be placed on its sides

1    8

9

3) solve for the final spots in the first row and the first column.

Row:

    1 + 8 = 9

    15 - 9 = 6

Column:

   1 + 9 = 10

   15 - 10 = 5

So,

1    8    6

9

5

3) Looking at the largest unused number, number 7, we can see that it is too large to go in the second row or the second column. This means it must be placed in the lower right corner

1    8    6

9

5          7

4) At this point you have enough information to solve for the rest of the numbers using simple addition and subtraction

TASK E5.1
1 The length, width and height of the cuboid are
measured to the nearest cm.
volume = length x width x height
What is the lowest possible value
of the volume of the cuboid?
Main Book Page 139
7 cm-
4cm
9cm

Answers

The length, width and height of the cuboid are measured to the nearest cm, volume = length x width x height,  the lowest possible value of the volume of the cuboid is [tex]cm^{3}[/tex].

What is volume?

Volume is measurement of three-dimensional space that is occupied. Numerous imperial units or the SI-derived units, such as the cubic meter and liter, are frequently used to quantify it numerically (such as the gallon, quart, cubic inch). Volume and length (cubed) have symbiotic relationship. The volume of a container is typically thought of as its capacity, not as amount of space it takes up. In other words, volume is the amount of fluid (liquid or gas) that the container may hold.

Volume was initially measured using naturally occurring vessels of a comparable shape and then with standardized containers. Arithmetic formulas can be used to quickly calculate volume of several straightforward three-dimensional shapes. If a formula for the shape's boundary is known, it is possible to use integral calculus to determine volumes of more complex shapes. No object in the dimensions of zero, one, or two has volume; in the dimensions of four and above, the hypervolume is a concept similar to the standard volume.

Volume = 7cm*4cm*9cm = 252[tex]cm^{3}[/tex]

To know more about volume visit: https://brainly.com/question/13338592

#SPJ9

is Figure C a scaled copy of Figure D (Thank you!)

Answers

yes it is because it’s a transformation

Answer:

Step-by-step explanation:

Figure D is a dialation of Figure C.

Each of the sides of Figure D is proportionate to Figure C

The scale factor is 1.5

3:2 = 4.5:3 = 3:2=3:2

Question
What numbers are a distance of 23 unit from 12 on a number line

Answers

Answer:

distance: 11

there are 11 points between 12 and 23, they are:

12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22 and 23.

Step-by-step explanation:

G(x)=-x^2/4+7

Over which interval does have a negative average rate of change?

Answers

Answer: [tex](-\infty, 0][/tex]

Step-by-step explanation:

This is a parabola that opens down (because of the negative leading coefficient).

So, the average rate of change (i.e., the slope of the secant) is negative when the function is decreasing.

The function is decreasing to the left of the vertex, which is at (0, 7).

So, the function has a negative average rate of change for [tex](-\infty, 0][/tex].

Note that although there is a stationary point at x = 0, and that the graph isn't decreasing at this point, the average rate of change is still negative when considering a point to the left.

Suppose sin a + cos b = -0.2 while sin b + cos a = 1.6. What is the value of sin(a+b)?

Answers

The value of the trignometric expression sin(a+b) is 0.3.

Given the trignometric equations sin a + cos b = -0.2 and sin b + cos a = 1.6

So, squaring both equations and adding them

we have

[tex](sin a + cos b)^2 = -0.2^2\\(sin a + cos b)^2 = 0.04\\sin^2a+cos^2b + 2 sina cos b= 0.04\\(sin b + cos a)^2 = 1.6^2\\sin^2b+cos^2a + 2 sinb cos a= 2.56\\\\[/tex]

adding both equations

[tex]sin^2a+cos^2b + 2 sina cos b + sin^2b+cos^2a + 2 sinb cos a= 0.04+2.56\\[/tex]

1+1+2( sina cos b + cos a sin b)= 2.6

2( sina cos b + cos a sin b) = 0.6

( sina cos b + cos a sin b) = 0.3

We know that sin(a+b)= ( sina cos b + cos a sin b)

So,

sin(a+b)=0.3

Therefore, the value of sin(a+b)  = 0.3

Learn more about trignometry here

https://brainly.com/question/17081568

#SPJ1

Trevor tutors French for $15 and hour and scoops ice cream for $10 an hour. He iS going to work 15 hours
this week. How many hours does Trevor need to tutor to make at least $180?
hours

Answers

Inequality - Trevor needs to tutor more than 6 hours in order to make at least $180.

What is inequality?

inequality, A declaration of an order relationship between two numbers or algebraic expressions, such as greater than, greater than or equal to, less than, or less than or equal to. Either questions or theorems can be used to express inequality problems, and both can be solved using methods similar to those used to solve equations. The triangle inequality, for instance, states that the length of the remaining side of a triangle is greater than or equal to the sum of the lengths of any two of its sides. Many of these inequalities, including the Cauchy-Schwarz inequality, are used by mathematical analysis to prove some of its most significant theorems.

Total number of hours = 15

Let the hours spent tutoring French is x

Therefor, hours spent in scooping ice cream = (15-x)

Tutoring French is $15 an hour, total for x hours = 15x

Scooping ice cream is $10 an hour, 10×(15-x)= 150-10x

To make more than $180,

= 15x+ (150-10x)> 180

= 15x+150-10x>180

=15x-10x>180-150

=5x>30

=x>6

So, Trevor needs to tutor more than 6 hours.

To learn more about inequality from the given link
https://brainly.com/question/24372553
#SPJ9

If you add Alex’s and bobs pie total together, they ate 22 pies, while bobs and chucks pies sum to 24. When you add Alex and chucks pie together, you find that they are 16 total. How many pies did each individual eat?

Answers

The number of pie each got-

Alex  -7Bob - 15Chuck - 9What is the method of elimination?To create an equation in one variable, use the elimination method and can either add or subtract this same equations. Whenever the coefficients with one variable are opposites, the equations are added to eliminate a variable; when the coefficients with one variable are equal, the equations are subtracted to eliminate a variable.

For the given question;

Let the number of pie eaten by Alex be 'a'.

Let the number of pie eaten by Bob be 'b'.

Let the number of pie eaten by Chuck be 'c'.

Then, for the given condition.

If you add Alex’s and bobs pie total together, they ate 22 pies,

a + b = 22 .....eq 1.

Bobs and chucks pies sum to 24.

b + c = 24   .......eq 2

Alex and chucks pie together be 16.

a + c = 16      .......eq 3

Solving equation 1 and 3 by elimination.

Subtract eq 3 from 1.

c = b - 6 .....eq 4

Solving equation 4 and 2.

b = 15

Put in eq 4

c = 9

Put the values of b and c in eq 1.

a = 7

Thus, the number of pie shared by Alex, Bob and Chuck are 7, 15 and 9 respectively.

To know more about the method of elimination, here

https://brainly.com/question/28405823

#SPJ10

multiply 2^3x^3.6^3x^3

Answers

The expression is multiplied to give 1728x^6

What are index forms?

Index forms are simply defined as the power or exponent of a variable, number or element.

It is also seen as an arithmetic method of writing numbers that are too large or too small into simpler forms.

The rules of exponents are;

Add the powers if they are being multiplied the bases are the sameSubtract the exponents if they are divided and have the same base.Multiply the exponents when the bases of the forms are the same

Given the expression;

2^3x^3.6^3x^3

We have to determine the product of the index forms

First, we have to multiply the numbers, we have;

2^3 = 2 × 2 × 2 = 8

6^3 = 6 × 6 × 6 = 216

Now, substitute the values

8x³ × 216x³

Multiply through

1728x^3 + 3

1728x^6

Thus, the value is 1728x^6

Learn more about index forms here:

#SPJ1

-1 1/3 - 1/6 subtract using number line

Answers

The addition of the two negative numbers has a result of -3/2, and is illustrated on the number line given at the end of the answer.

How to add two negative numbers?

To add two negative numbers, we keep the negative signal and then we add the quantities, that are represented by the numbers without the signal.

For this problem, the numbers are given as follows:

-4/3, which is the mixed number -1 and 1/3, given by -1 - 1/3 = -3/3 - 1/3 =  -4/3.The fraction -1/6.

Hence the addition of the negative numbers is given as follows:

-4/3 - 1/6 = -8/6 - 1/6 = -9/6 = -3/2.

The result is of -3/2.

As for the number line, we have two negative numbers, hence each increment is to the left of the number line. The sum of the two increments, starting at zero, of 1/6 and of 4/3, combine to 3/2, as given by the image at the end of the answer.

More can be learned about the addition of the two negative numbers at https://brainly.com/question/604854

#SPJ1

-2x + 3y = -6 and -3x - 2y = 11

Answers

Step-by-step explanation:

-2x + 3y = -6

-3x - 2y = 11

-5x + y = 5

y = 5 + 5

y = 10

-2x + 3(10) = -6

-2x + 30 = -6

-2x = -6 - 30

-2x = -36

x = -18

i have no idea

2-b/3= -5/2 if you guys can help me thank you very much.

Answers

Answer:

b = 13.5

Step-by-step explanation:

2-b/3 = -5.2Multiply both sides of the equation by 6, the least common multiple of 3,212 - 2b = -15Subtract 12 from both sides-2b = -15 - 12Subtract 12 from -15 to get -27-2b = -27Divide both sides by -2b = -27/-2You can simplify -27/-2 by dropping off the negative sings making it b = 27/2Divide 27/2 to get 13.5 Or you can just simplify 27/2 to 13 1/2

There are different ways you can solve this equation. Let me know if you'd like to know a different way.

Have a Good Rest of Your Day.

A cylindrical container is to be constructed so that the sum of its height and its diameter is 15 feet.
a) Write an equation relating the height of the cylinder, h, to its radius, r. Solve the equation for h in terms of r.
b) The volume of a cylinder is given V=πr^2h. Use your answer in part A to express the volume of the cylindrical container in terms of r alone. Leave your expression in factored form so that it will be easier to analyze.
c) What are the values of r for which this problem makes sense? Explain.

Answers

From the characteristics of the given cylinder, we have that:

a) The equation is h = 15 - 2r.

b) The volume of the cylinder is of V = πr²(15 - 2r).

c) The values of r should be in the range of 0 < r < 7.5.

What is the volume of a cylinder?

The volume of a cylinder of radius r and height h is given according to the following equation:

V = πr²h.

The sum of the height and the diameter is of 15 feet, hence:

h + d = 15.

The diameter is twice the radius, hence:

h + 2r = 15.

For item a, the solution of h in terms of r is:

h = 15 - 2r.

Hence, in item b, the equation is:

V = πr²h.

V = πr²(15 - 2r).

For item c, there are two constraints, as follows:

r > 0, as the radius of a cylinder cannot be negative nor zero.r < 7.5, as the height must be positive.

More can be learned about the volume of a cylinder at https://brainly.com/question/9554871

#SPJ1

-3x= 2x^2 -4 solve using quadratic formula

Answers

Solution of the given equation -3x =2x² -4,using quadratic formula is (-3 ±√41) /4.

As given in the question,

Given equation is:

-3x =2x² -4

Rearrange the terms in proper order:

2x² + 3x -4 =0

Solve it using quadratic formula

x = (-b ±√b²-4ac)/ 2a

Here compare the given equation with general quadratic equation:

a =2 , b=3 , c=-4

Substitute the values in the quadratic formula we get,

x = [ -3± √(3)² -4(2)(-4)]/2(2)

  = (-3 ± √9+32)/4

  = (-3 ±√41) /4

Therefore, Solution of the given equation -3x =2x² -4, using quadratic formula is (-3 ±√41) /4.

Learn more about quadratic formula here

brainly.com/question/9300679

#SPJ1

what is 1+1x3/2+10x3450/2+300-500 I don't know what is it

Answers

Answer:

17052 1/2

You're Welcome

Write an equation for the line through the points (6, 10) and (3, 5) in point-slope form.
y =
+

Answers

Point slope form of the equation through the points (6, 10) and (3, 5)  is y - 5 = 5/3 (x - 3)

Point slope form:

The point slope form of equation is used to find the equation of the straight line which is inclined at a given angle to the x-axis and passes through a given point.

The general form of the equation is

(y - y1) = m (x - x1)

y = y coordinate of second point

y1 = y coordinate of point one

m = slope

x = x coordinate of second point

x1 = x coordinate of point one

Given,

Here we have the points  (6, 10) and (3, 5).

Through the given points we have to find the point slope form of the equation.

To find the point slope of the equation, first step is to find the slope of those points,

It can be calculated using the formula,

m = (y2 - y1)/(x2 - x1)

Where the values of (x1,y1) is (6,10) and the values of (x2,y2) is (3,5).

Then the value of slope after applying the values,

m = (5 - 10)/(3-6)

m = -5/-3

m = 5/3

Use the slope and a given point (3,5) to substitute for x1 and y1 in the point-slope form

y−y1=m(x−x1),

which is derived from the slope equation.

Then we get the equation as,

y - 5 = 5/3 (x - 3)

Therefore, the point slope form equation is y - 5 = 5/3 (x - 3).

To know more about Point Slope form here.

https://brainly.com/question/12743204

#SPJ1

a researcher is interested in the travel time of utrecht university students to college. a group of 50 students is interviewed. their mean travel time in 16.7 minutes. for this study the mean of 16.7 minutes is an example of a:

Answers

For this study, the mean of 16.7 minutes is an example of a (B) Statistic.

What do we mean by Statistic?As opposed to methods for gathering statistical data, mathematical statistics is the application of probability theory, a subfield of mathematics, to statistics. Mathematical analysis, linear algebra, stochastic analysis, differential equations, and measure theory are some of the specific mathematical methods used in this. Due to the abstract concepts and ideas that you will encounter later in your study, statistics stands out as the more challenging area of math. When you actually try to understand what's happening in a statistics equation or problem, you'll discover that the concepts are very challenging.

So, the appropriate choice is an option (B).

In this case, a researcher is interested in how long it takes Utrecht University students to get to class. For this study, a sample of 50 students was gathered, and the sample mean for travel time was found to be 16.7 minutes.Since the sample means is a sample statistic, option (B) is the right choice.

Therefore, for this study, the mean of 16.7 minutes is an example of a (B) Statistic.

Know more about Statistics here:

https://brainly.com/question/27061777

#SPJ9

The correct question is given below:
A researcher is interested in the travel time of Utrecht University students to college. A group of 50 students is interviewed. Their mean travel time in 16.7 minutes. For this study, the mean of 16.7 minutes is an example of a(n)

A. Parameter

B. Statistic

C. Population

D. Sample.

0.0158 rounded to the nearest tenth

Answers

Answer:

Step-by-step explanation:

step by step 9 divided by 1557

Answers

Answer:

0.00578034682

Step-by-step explanation:

9/1557

keep on adding .0 to the end of your number.

You will eventually get the answer.

Answer:

173.

Step-by-step explanation:

if c=4 work out the value of
c/2 + 6

Answers

Using arithmetic operations, If the value of c = 4 then the value of (c/2) + 6 is 7

The given expression is (c/2) + 6

The value of c = 2

To find the value of (c/2) + 6 we have to do the suitable arithmetic operation after substituting the value  c in the expression

Substitute the value of c in the given expression (c/2) + 6

(c/2) + 6 = (2/2) + 6

Divide 2 by 2 first

(2/2) + 6 = 1+6

Add one and six

1+6 = 7

Hence, by using the arithmetic operation, if the value of c = 4 then the value of (c/2) + 6 is 7

Learn more about arithmetic operation here

brainly.com/question/3075170

#SPJ1

find the compound interest on $1500 for 2years at 2%per annum compounded anually

Answers

Answer:

$1560.60

Step-by-step explanation:

PV (1+V)^n

= 1500 (1+2%)² = 1560.6

Do the ratios 9 6 and 12 8 form a proportion?

Answers

The ratios 9:6 and 12:8 does not form a proportion, since the products of the two are not equal.

Given we have two ratios:

9:6 and 12:8

An equation in mathematics that shows that two ratios expressed in fraction form are equivalent is known as a proportion. The rule that says a/b= c/d if and only if ad=bc allows us to assess whether two ratios, a: b and c: d, constitute a proportion.

To determine if 9:6 and 12:8 form a proportion, we use the rule of proportion.

That is, 9/12 = 8/6

If only if 9×6=12×8

Therefore,  9×6=54

and 12×8=96

since these two products are not equal, we have that 9:12 and 8:6 do not form a proportion.

Hence the ratios 9:6 and 12:8 are not in proportion.

Learn more about ratio and proportion here:

brainly.com/question/19994681

#SPJ1

what is the answer to (b+3f)a=g

Answers

Answer:

f= -g/3

Step-by-step explanation:

34= -w/7 solve for w

Answers

Hey! Your question was incomplete because I have double-checked my work, and even checked reliable sources to see if I missed something in my work, but I keep getting –238. I did play around with the question by switching the negative symbol around in the equation to see if I would get a balanced answer. I say this because when you solve the question you posted, the answer I got was w = –238, but when I went back to check my work by plugging that number in as the value of w, I got –238 ≠ 238 (or something like that. The number is the same, but the signs are not). If the signs and numbers don't both equal each other something is wrong with the problem. I believe I figured out where your question went wrong. Instead of the question being 34 = –w/7, I believe that the correct question should have been –34 = w/7. What I think happened was that when you typed your question, you swapped the negative on the 34 with the variable of w. If I am incorrect, and you typed your question correctly, I am sorry in advance because my work wasn’t matching what I got for w. But for now, I will solve what I think the question should have said. Again, sorry in advance. Solve for w in the following equation: –34 = w/7.

Write the equation:

–34 = w/7

Multiply both sides by 7:

7 × –34 = w/7 × 7

Multiply:

–238 = 1w

Divide:

–238/1 = 1w/1

–238 = w or w = –238

Check your work by plugging –238 back into the equation as w:

–34 = w/7

–34 = –238/7

Multiply both sides by 7:

–34 × 7 = –238/7 × 7

–238 = –238 ✔

Thus, w = –238

Hope that helps! Have an amazing rest of your day!! :)

Other Questions
The city is issuing bonds to raise money for a building project. You obtain a $4100 bond that pays 6% interest annually that matures in 8 years. How much interest will you earn? What is the gradient of the straight line shownbelow? Let f= {(1,2),(2,3),(3,5),(4,7)}What is f f 100 POINTS PLEASE ANSWER ASAP! Why does a food like a marshmallow have so little energy? X If I want to measure the mass of a fly in metrics, What should I use 1.1 A tuck shop at a particular school sells soft drink cans. The economic friendly club of this school collected soft drink cans for recycling for a period of 20 days. The number of cans collected was recorded and the data is given below: 48 50 52 59 60 68 73 76 76 76 78 79 80 81 82 82 84 91 92 98 1.1.1 Determine the median of the cans collected. 76 91 76 92 76 98 (1) A plot of land measure 25m by 12cm .A portion of this plot measuring 8m by 8m is used for cultivation of vegetable find the area of the plot not cultivated. How much is +7 - 4?Number line: -15 to +15A.3B.11C.-11D.-3_________What is the value of +3 - 8?Number line: -15 to +15A.-11B.-5C.5D.11________ What is the value of 5 - 12?Number line: -15 to +15A.7B.-17C.17D.-7______What integer is the result of moving 10 units in a positive direction, starting at -6?Number line: -15 to +15A.-16B.4C.16D.-4 a leader who is willing to assert themselves, be proactive, and can persevere through adversity demonstrates which key trait? determination sociability confidence intelligence my children are my plants. i must nurture them to grow. what Type of figurative language is it. container a holds 4 red balls and 6 green balls; containers b and c each hold 6 red balls and 4 green balls. a container is selected at random and then a ball is randomly selected from that container. what is the probability that the ball selected is green? express your answer as a common fraction. the rate constant for this secondorder reaction is 0.850 m1s1 at 300 c. aproducts how long, in seconds, would it take for the concentration of a to decrease from 0.910 m to 0.340 m? How did limiting voting rights to white male landowners affect Americans in 1776? It provided opportunities for all Americans to succeed. It allowed Americans to form an independent nation.The promise of equality did not extend to most Americans.Independence from British rule did not extend to most Americans. What's the Normal Force in Newtons for a 2,899 kg Warthog that Master Chief is driving while fighting off a horde of angry aliens? Assume the Halo installation the vehicle is on has an acceleration due to gravity of 10 m/s squared (or same as Earth). In 1909, scientist ernest rutherford directed a stream of high speed alpha particles at a thin piece of gold foil. Some of the particles passed through, some were deflected, and some bounced straight back. This result caused rutherford to conclude that. Compare and contrast the outsiders movie to the book, PLEASE ANSWER AND HELP MEEEE !! ill make you as the brainliest and give you a 5 star rating please please please help !!!!!! 57Diagram notdrawn accurately(i) Work out the size of the angle marked p. You purchase $7,000 from a store offering 10% down, no interest if paid in full by three months.$5,000 is paid before deadline, how much is owed if monthly interest is 2.49%?Owed: $____________ The cells of the cheek become blue when the stain methylene blue is added which property of the cell membrane does this show