If 18 g of a radioactive substance are present initially and 9 yr later only 9 g remain, how much of the substance will be present after 12 yr?
After 12 yr there will be g of a radioactive substance.
(Round the final answer to three decimal places as needed. Round all intermediate values to seven decimal places as needed.)

Answer:

450 min hope this helps!

Step-by-step explanation:

Answer

It will take him 450 minutes to read 90 pages.

Explanation

Luis can read 3 pages every 15 minutes.

You are trying to find how long it will take him to read 90 pages.

Set up this ratio.

[tex]\frac{15}{3} =\frac{x}{90}[/tex]

To get from 3 to 90, you multiply by 30. Do the same thing to 15.

15 times 30 is 450.

It will take Luis 450 minutes to read 90 pages.

Answer:

400 square feet

Step-by-step explanation:

20 x 20 = 400

HOPE THIS HELPS

PLZZ MARK BRAINLIEST

Answer:

400 square feet

Step-by-step explanation:

Area = length x width

A = lw

A = 20 x 20

20 x 20 = 400

Area = 400 ft^2

Answer:

The car dealer must sell 105 cars in May to reach his goal.

Step-by-step explanation:

Given that the car dealer sold 84 cars in April, and wants to increase his May sales by 25%, to determine the number of cars he must sell to reach his goal it is necessary to perform the following calculation:

84 + (84 x 0.25) = X

84 + 21 = X

105 = X

Therefore, the car dealer must sell 105 cars in May to reach his goal.

Answer:

S(50) = 0

Step-by-step explanation:

The initial condition is S(0) = 0, so start at the origin.  The slope there is approximately 1.  So as t increases by a small amount, S increases by the same amount.  Continuing this logic, we end up tracing the vector field until we get to t=50, where S is approximately 0.

Each little tickmark is a slope value telling you which direction to go. If you place yourself at the origin (0,0) then the tick mark here tells us to go roughly in the northeast direction. As you step forward to the northeast just a tiny bit, the slope value changes to aim more toward the east (rather than north). For more information, check out Euler's method. Specifically it's Euler's method dealing with slope fields.

The diagram below shows what could be each step of this process. Each red dot is a stepping stone, so to speak, going from (0,0) to (50,0). This is an approximation. Without the actual function F(t, S), it's hard to say where exactly S(50) is located. But S(50) = 0 is a fairly good guess I think. MathPhys has a great diagram showing what could be the solution for S(t) given the initial condition S(0) = 0. Note how they drew a curve through all of the red points I've marked.

9514 1404 393

Answer:

  400207

Step-by-step explanation:

Any calculator can form this sum for you. It is ...

  4×10^5 +2×10^2 +7

  = 400,000 +200 +7

  = 400207

Answer:

2 ninths, or 2/9

Step-by-step explanation:

Multiply -2/3 by -1/3 to get the answer

Answer: f=2/9

you have to multiply 2/-3 and -3/2f

Trust me it will work

Answer:

Step-by-step explanation:

Perimeter formula

Solving for w

Option B is correct

Answer:

y-intercept: [tex]y=0[/tex]

axis of symmetry: [tex]x=0[/tex]

vertex: [tex](0,0)[/tex]

Step-by-step explanation:

To find the y-intercept, set x = 0 and solve for y.

I am assuming f(x) = y

[tex]y=4x^2[/tex]

[tex]y=4(0)^2[/tex]

[tex]y=0[/tex]

The y-intercept of the equation is y = 0.

Now, for the axis of symmetry, you need the equation [tex]x=\frac{-b}{2a}[/tex]

In an equation.. [tex]y=ax^2+bx+c[/tex]

In this case, there is only an a, so plug in the values into the equation.

[tex]x=\frac{0}{2(4)}[/tex]

[tex]x=0[/tex]

The axis of symmetry is x = 0.

To find the vertex, change the format of the equation from standard form to vertex form.

Vertex form: [tex]y=a(x-h)^2+k[/tex]

The vertex is [tex](h,k)[/tex]

[tex]y=4x^2 = 4(x+0)^2+0[/tex]

[tex](h,k)=(0,0)[/tex]

The vertex in this case is (0,0).

Graphing makes things a lot easier. If you can graph it, all you have to do is look at the graph and the answers are all there!

Hope this helped you!

Answer:

B. (2, 2)

Step-by-step explanation:

The coordinate (2, 2) is the only thing they share in common, both lines intersect each other on that coordinate.

Answer:

first answer is 9.84

Step-by-step explanation:

9.84 is the square root of 97, rounded to the nearest hundredth.

the legs measure 9 x 9 and 4 x 4 = 81 and 16.

81 + 16 = 97, so your answer is the square root of 27, which rounded to the nearest hundredth, equals 9.84. Rounding towards the nearest whole, 10 would be your best bet.

hope this helps!!

y = 3x² + 1

Differentiate both sides with respect to t :

dy/dt = 6x dx/dt

We're given that dy/dt = +3 units/second, so when x = 2 we find

3 u/s = 6 • 2 dx/dt

dx/dt = 3/12 u/s = 1/4 u/s

which means x is increasing at a rate of 1/4 units per second.

Answer:

12 pounds

Step-by-step explanation:

Please give me thanks

When you give me thanks

Have a good day :)

The weight of the baby at birth is 8 pounds.

Given,

The weight, in pounds, of a newborn baby tt months after birth, can be modeled by W.

The table below has select values showing the linear relationship between

t and W.

We need to determine the weight of the baby at birth.

The table is given as:

1         10

4.5     17

9        26

The table has two columns and it always has a relationship between them depending on the question.

Example:

Miles.        Hours

2.               3

6.               9

8.               12

Here we see that every 1-5 hours there's a mile increase.

We have,

W = weight of the baby

t = number of months.

From the table:

The baby weight-

At 1 month = 10

At 4.5 months = 17

At 9 months = 26

We see that,

In,

(4.5 - 1) = 3.5 months there is an increase of (17 - 10) = 7 pounds.

So we can write it as:

3.5 months = 7 pounds

1 month = 7/3.5

1 month = 70/35 = 10/5 = 2 pounds

This means in after every month there is an increase of 2 pounds.

We have,

1In the first month, the weight of the baby is 10 pounds.

And every month there is an increase of 2 pounds.

So,

The weight of the baby at birth is:

= 10 - 2

= 8 pounds

Thus the weight of the baby at birth is 8 pounds.

Learn more about finding relationships in a given table here:

https://brainly.com/question/28350476

#SPJ2

Answer:

tan(arrcos( -√2 /2)) = -1

(result in radians)

Step-by-step explanation:

Answer:

5304

Step-by-step explanation:

hope it helped

Answer:

5304

Step-by-step explanation:

You can use the distributive property to solve for this

To “distribute” means to divide something or give a share or part of something. According to the distributive property, multiplying the sum of two or more addends by a number will give the same result as multiplying each addend individually by the number and then adding the products together.

Have a good day!

Answer:

8400p.

Step-by-step explanation:

I'm assuming you're asking about the total price of the loaves here. Please specify your question further next time.

(84*100)p

= 8400p

Hope that helped!

Slope = 2

x-intercept = 8/2 = 4

y-intercept = 8/-1 = -8.00000

answer : 8.00000

Answer: y=2x-8

Slope 2 initial value I’m guessing is the y intercept which is -8

Step-by-step explanation:

12x-6y=48

-12x -12x

-6y=-12x+48

Divide by -6

Y=2x-8

Complete Question

The complete question is shown on the first uploaded image

Answer:

The value is  [tex]P( 1.39 < z < 1.53 ) = 0.0193[/tex]

Step-by-step explanation:

From the question we are told to obtain the area to the of the z-score 1.39 and to the left of the z-score 1.53, this is mathematically represented as

        [tex]P( 1.39 < z < 1.53 ) = P( z < 1.53 ) - P( z < 1.39 )[/tex]

From the z table on the question the area under the normal curve to the left corresponding to 1.53 and  1.39  is

       [tex]P( z < 1.53 ) = 0.9370[/tex]

and

      [tex]P( z < 1.39 ) = 0.9177[/tex]

So

     [tex]P( 1.39 < z < 1.53 ) = 0.9370 - 0.9177[/tex]

=>  [tex]P( 1.39 < z < 1.53 ) = 0.0193[/tex]

Answer:

Since slope of line y = 0 and y = 4

Step-by-step explanation:

Given:

y = 4

Computation:

Equation of slope;

y = ax + c

So,

y = (a)(0) + 4

Since slope of line y = 0 and y = 4

Answer:

y=0

Step-by-step explanation:

Answer:

In the image, we can see that the arrows go from the negative pole to the positive pole.

This image then represents the flow of electrons in the situation (Remember that we define current as the flow of "holes", so current is usually defined in the opposite direction than the flow of electrons).

Second question:

In a current, the electrons usually do not move really fast (in average velocity).

Now, the current flowing in a given material will depend mostly on:

The area of the material (a cable with larger diameter can have a larger electricity than a thin cable) and the material itself (there are some materials that are really good conductors, and there are materials that are bad conductors)

Now, this concept of good/bad conductor can be thought as follows,

A bad conductor has a lot of particles (for example electrons in the inner energy levels) in the way of the flow of electrons, and when the electrons want to move, they may interact with those particles, and then the flow of electrons is diminished.

For a good conductor, those particles do not interact, and there are not a lot of these particles. (Also good conductors have more electrons in the valence level, so there are more electrons that can flow in the material).

Another important factor is the temperature of the material, we know that when we increase the temperature of a material, the particles of this material will have an increment in its kinetic energy, then those particles will be moving a lot, and there is a larger possibility that there will be an interaction with the flowing electrons.

In the case where the object is really cold, the kinetic energy of the particles will be small, and these will be more "ordered", which helps with the current flow.

Then we can conclude that the electricity does not really depend on the speed of the electron, it depends more of the material of the conductor and the cross-section area.

Answer:

1,128

Step-by-step explanation:

94 x 12 = 1,128

what hy7h7yh

Answer:

1128 inches.

Step-by-step explanation:

12 inches = 1 feet

94 * 12 = 1128

-2(y-1) = 9

Use distributive property:

-2y + 2 = 9

Subtract 2 from both sides

-2y = 7

Divide both sides by-2:

Y = -7/2

Answer:

2.3/14              4.-4 3/8

6.1/11                 8. 1/10

10.1/8                 12. 4/7

14.-2  8/9           16. 22

18.10 2/3            20. 2 4/7

Step-by-step explanation:

I feel like it will take me forever to explain but you should head to a site like Khanacademy to explain the topic or perhaps if this is homework ( and I just gave you answers for it ;-;) you should ask your teacher

Hopefully I was helpful

Love yall!

Answer: You can have about 13 loafs of pumpkin bread.

Step-by-step explanation: 3/4 is the same as 0.75 so you will add 0.75 to 0.75 13 times

0.75+0.75+0.75+0.75+0.75+0.75+0.75+0.75+0.75+0.75+0.75+0.75+0.75=13.33.

13.3 is not a whole number so you will say 13.

Answer:

Ones place

Step-by-step explanation:

Hope this helped, Have a Wonderful Day/Night!!

Answer:

yes

no

no

Step-by-step explanation:

Answer:

Increased on the test more than the quiz

Step-by-step explanation:

If we do 21/27, we get 0.77777777777, as a percent, 0.77.

Then we do 66/80, and get 0.825, as a percent, 0.82.

We can already tell that she did better on the test, than the quiz.

Answer:

x = 4

Step-by-step explanation:

-5/6x = -10/3

x = -10/3 / -5/6

x = 4

Topic: algebraic equations

If you like to venture further, feel free to check out my insta (learntionary). I'll be constantly posting math tips and notes! Thanks!

Answer:

4(3a+5)

Step-by-step explanation:

When you factor an algebraic expression, you divide the initial expression by a common factor to produce your answer.

have a gr8 day (:

Answer:

40 questions

Step-by-step explanation:

38=.95x where x is the total tests

38/.95 = x

40 = x