Scientists learn more about the natural world through investigation. This involves identifying a problem, researching related information, designing and conducting an investigation, analyzing the results, evaluating the conclusion, and communicating the findings. Engineers follow similar steps when creating new products or solutions through technological design. The four stages of technological design include identifying a need, designing and implementing a solution, and evaluating the solution.

Answer: b. social contract

Explanation:

This text in the Declaration of Independence is influenced by John Locke's Social Contract theory which believes that people only enact a government that will keep them safe and secure to allow them pursue their daily lives with liberty.

If the government is unable to do that then the people have the right to overthrow such a government and institute a new one that will act in such a way as to bring them safety and happiness.

Answer:

Social Contract is right but the letter for mine was c whether the letter is different the social contract is correct.

Explanation:

Answer:

true ...............

Some refrigerants R11, R12, and R115 contain CFC. The statement is true.

Chlorofluorocarbons (CFCs), as the name suggests, are compounds made of the atoms of fluorine, chlorine, and carbon. Because they are neither hazardous nor combustible, they have a variety of uses, including in refrigeration. Refrigeration is the process of maintaining the temperature of the required space cooler than that of an atmosphere.

As the public learned in 1974 that CFCs were alarmingly destroying the ozone layer, most CFCs were outlawed, and by 1995, their manufacture of them had virtually ended worldwide.  CFCs were replaced with other products since they were no longer produced and the things they were used for required new products.

Therefore, some refrigerants R11, R12, and R115 contain CFC. The statement is true.

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Answer:

V = 50 ft³/s

H.P = 0.466

Explanation:

Given that

Diameter of the duct, D = 0.3 m

Vacuum Pressure of the duct, Z = 0.025 m

P(w) = pressure of water, 1000 kg/m³

P(a) = pressure of air, 1.22 kg/m³

To find the pressure change we use the formula

ΔP = P(w) * g * Z

ΔP = 1000 * 9.8 * 0.025

ΔP = 245 Pa.

We need the area, do we find that too

A = πd²/4

A = π * 0.3² * 1/4

A = 0.071 m²

Recall the energy equation to be

1/2v² = ΔP/p(a) , so that if we rearrange, we have

v² = 2ΔP/p(a)

v = √(2ΔP/p(a)), on substituting the values, we have

v = √(2 * 245)/1.22

v = √490/1.22

v = √401.64

v = 20.04

The volume flow rate is then equal to

Velocity * Area.

V = 20.04 * 0.071

V = 1.42 m³/s, converting to ft³/s, we have 50 ft³/s

Horsepower output is gotten using

P = ΔP * V

P = 245 * 1.42

P = 347.9 w, converting this to HP, we have 0.466 HP

Answer:

3.4 inches

Explanation:

Determine the diameter required to protect the vessel from a regulator failure ( relief diameter )

A = [tex]\frac{\pi d^2}{4}[/tex]

Hence d = [tex]\sqrt{\frac{4A}{\pi } }[/tex]  =  [tex]\sqrt{\frac{4 * 9.08}{\pi } }[/tex]  = 3.4 inches

attached below is the remaining part of the solution

Answer:

Contactors can be field mounted easily and are compact in size. Generally, these electrical devices feature multiple contacts. These contacts are in most cases normally open and provide operating power to the load when the contactor coil is energized. Contactors are most commonly used for controlling electric motors.

Explanation:

Answer:

d

Explanation:

yea

Answer:

D

Explanation:

Answer:

num_count = 0

while num_count < 25:

   print(num_count)

   num_count += 3

Explanation:

A while loop statement is defined in the python source code above. An integer variable 'num_count' is defined and continuously incremented by three in the loop until it is greater than 25. the output of the while loop between 1 and 25 is print on the screen.

Answer: Civil engineering is a branch in engineering which deals with design, construction, and building structures such as dam, bridges etc....

Explanation:

Answer:A rear disc/drum parking brake uses the inside of each rear wheel hub and rotor assembly as a parking brake drum

Explanation:

The interior of each rear wheel hub and rotor assembly serves as a parking brake drum in a rear disc/drum parking brake.

A drum brake is a type of brake that relies on friction created by a set of shoes or pads pressing outward against a rotating cylinder-shaped part known as a brake drum.

Drum brakes are commonly used to describe brakes in which shoes press against the inner surface of the drum.

Drum brakes provide consistent braking force regardless of whether the vehicle is moving forward or backward.

This is due to the fact that drum brakes produce the same braking force in both directions. This type is typically found on passenger car rear brakes.

Thus, in a rear disc/drum parking brake, the interior of each rear wheel hub and rotor assembly serves as a parking brake drum.

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Answer:

5 multiply by 10 S/M

Based on the calculations, the incident wave would be down to 1 mV/m at a depth of 287.82 meters.

Since the medium is a wet soil, it is characterized by the following:

Next, we would determine loss tangent, so as to know if the wet soil is a low-loss medium:

For a low-loss medium; ε''/ε' = σ/ωε < 0.01.

[tex]\frac{\sigma}{\omega \epsilon} = \frac{5 \times 10^{-4} \;\times\; 36 \pi}{2\pi \;\times \;3 \times 10^9\; \times\; 10^{-9} \times \;9} \\\\\frac{\sigma}{\omega \epsilon} =3.32 \times 10^{-4}[/tex]

Therefore, the wet soil medium is a low-loss dielectric and its absorption (attenuation) coefficient is calculated by using this formula:

Note:

[tex]\alpha = \frac{\sigma}{2}\sqrt{\frac{\mu}{\epsilon}} \\\\\alpha = \frac{\sigma}{2} \times \frac{120\pi}{\sqrt{\epsilon_r} } \\\\\alpha =\frac{5 \times 10^{-4} \times 120\pi}{2 \times \sqrt{9} } \\\\[/tex]

α = 0.032 Np/m.

Now, we calculate the depth:

[tex]E(z) = E_oe^{-\alpha z} = 10e^{-\alpha z}\\\\10^{-3}=10e^{-0.032 z}\\\\ln(10^{-4})=-0.032 z\\\\-9.21 \times 10^9=-0.032z\\\\z=\frac{-92.1 0}{-0.032}[/tex]

z = 287.82 meters.

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Answer:

Subcritical

Explanation:

To compute the grouse number

We use this formula

F = v/√gy

From this question

V = 1 m

G = 9.81m/sec²

Y = 0.5

When we insert this into the grouse formula

F = 1m/s / √ 9.8m/sec² x 0.5m

= 0.451< 1

Therefore we conclude that the grouse is less than 1 and so the flow is subcritical.

Answer:

SIR IT IS D HOPE THIS HELPS (☞ﾟヮﾟ)☞☜(ﾟヮﾟ☜)

Explanation:

Answer: The net force in every bolt is 44.9 kip

Explanation:

Given that;

External load applied = 245 kip

number of bolts n = 10

External Load shared by each bolt (P_E) = 245/10 = 24.5 kip

spring constant of the bolt Kb = 0.4 Mlb/in

spring constant of members Kc = 1.6 Mlb/in

combined stiffness factor C = Kb / (kb+kc) = 0.4 / ( 0.4 + 1.6)  = 0.4 / 2 = 0.2 Mlb/in

Initial pre load Pi = 40 kip

now for Bolts; both pre load Pi and external load P_E are tensile in nature, therefore we add both of them

External Load on each bolt P_Eb = C × PE = 0.2 × 24.5 = 4.9 kip

So Total net Force on each bolt Fb = P_Eb + Pi

Fb = 4.9 kip + 40 kip

Fb = 44.9 kip

Therefore the net force in every bolt is 44.9 kip

Answer:

b. American Society of Mechanical Engineers

Explanation:

The "American Society of Mechanical Engineers" (ASME) is an organization that ensures the development of engineering fields. It is an accreditation organization that ensures parties will comply to the ASME Boiler and Pressure Vessel Code or BPVC.

The BPVC is a standard being followed by ASME in order to regulate the different pressure vessels and valves. Such standard prevents boiler explosion incidents.

The answer is explained in the picture. Thank you. Rate it

Answer:

I think is B

Explanation:

Answer:

A) complex power = apparent  power =  ( 108.253 + 62.5 i ) VA  

    active power = 108.25 watts

   reactive power = 62.5 VAR'S

    power factor = cos ∅ = cos 30° = 0.866 ( lagging )

also ; current lags voltage by 30°

B) your question is not well written hence no answer

Explanation:

A) v(t) = 100 cos (377t - 30° ) v

    Vrms = [tex]\frac{100}{\sqrt{2} }[/tex] ∠ -30°

    I(t) = 2.5cos(377t- 60°) A

  Irms = [tex]\frac{2.5}{\sqrt{2} }[/tex] ∠ -60°

determine complex power apparent power . ......  power factor

Note : complex power = apparent power

=( Irms ) * Vrms

=  ( [tex]\frac{2.5}{\sqrt{2} }[/tex] ∠ -60° ) * ( [tex]\frac{100}{\sqrt{2} }[/tex] ∠ -30° )  

= 125 ∠ 30°

= ( 108.253 + 62.5 i ) VA   ( complex power )

active power = 108.25 watts

reactive power = 62.5 VAR'S

power factor = cos ∅ = cos 30° = 0.866 ( lagging )

current lags voltage by 30°

Answer:

A) approximate alkalinity = 123.361 mg/l

B) exact alkalinity = 124.708 mg/l

Explanation:

Given data :

A) determine approximate alkalinity first

Bicarbonate ion = 120 mg/l

carbonate ion = 15 mg/l

Approximate alkalinity = ( carbonate ion ) * 50/30  + ( bicarbonate ion ) * 50/61

                                   = 15 * (50/30) + 120*( 50/61 )  = 123.361 mg/l  as CaCO3

B) calculate the exact alkalinity of the water if the pH = 9.43

pH + pOH = 14

9.43 + pOH = 14. therefore pOH = 14 - 9.43 = 4.57

[OH^- ] = 10^-4.57  = 2.692*10^-5  moles/l

[ OH^- ]   = 2.692*10^-5  * 179/mole * 10^3 mg/g  = 0.458 mg/l

[ H^+ ] = 10^-9.43 * 1 * 10^3  = 3.7154 * 10^-7 mg/l

therefore the exact alkalinity can be calculated as

= ( approximate alkalinity ) + ( [ OH^- ] * 50/17 ) - ( [ H^+ ] * 50/1 )

= 123.361 + ( 0.458 * 50/17 ) - ( 3.7154 * 10^-7 * 50/1 )

= 124.708 mg/l

Answer:

Answer: B) Scanning the computer and deleting any viruses.

Explanation:

Some of the feedback I hear from new developers working on a programming problem revolves around uncertainty of where to start. You understand the problem, the logic, basics of the syntax, etc. If you see someone else’s code or have someone to guide you, you can follow along. But maybe you feel uncertain about doing it yourself and have trouble turning your thoughts into code at first even though you understand the syntax or logic. Here’s my process and some tips to tackling a sample problem that hopefully some of you may find helpful in your journey.

If you need further expenation then:

Some of the feedback I hear from new developers working on a programming problem revolves around uncertainty of where to start. You understand the problem, the logic, basics of the syntax, etc. If you see someone else’s code or have someone to guide you, you can follow along. But maybe you feel uncertain about doing it yourself and have trouble turning your thoughts into code at first even though you understand the syntax or logic. Here’s my process and some tips to tackling a sample problem that hopefully some of you may find helpful in your journey.

May i please have brainliest

Answer:

B. scanning the computer and deleting any viruses

Explanation:

I took the test on edge, and this makes most sense to me. Good luck:)

This question is incomplete, the complete question is;

An individual eats fish from a river contaminated with benzene. What concentrations of benzene in water (mg/L) would produce a lifetime cancer risk of 10⁻⁶ to an individual who eats 2 meals of fish per week for 30 years if the BCF for benzene is 10⁺³?

Answer:

0.021 mg/L concentration of benzene in water  would produce a lifetime cancer risk 10⁻⁶ to an individual who eats 2 meals of fish per week for 30 years if the BCF for benzene is 10⁺³

Explanation:

Chronic daily intake (CDI) =(C/W) (Intake rate/ lifetime) ( Exposure)

values from EPA Exposure Factors Table)

CDI = [ (5.2 L/d × C mg/L  0.054 kg/d) / 70 kg] [30/70] [350/365]

CDI = 1.65 × 10⁻³C

Now concentration of benzene;  ( RISK) = CDI × pF

= 10⁻⁶ = [2.9× 10⁻² / (MG/kg-d)] ( 1.65 × 10⁻³C)

C = 0.021 mg/L

Therefore 0.021 mg/L concentration of benzene in water  would produce a lifetime cancer risk 10⁻⁶

Answer:

10

Explanation:

The speed of the chain is the same for both sprockets.

vᵢ = vₒ

ωᵢ rᵢ = ωₒ rₒ

The sprockets have the same pitch, so the radius is proportional to the number of teeth.  So we can say:

ωᵢ nᵢ = ωₒ nₒ

Plugging in values:

(60 rpm) (40) = (240 rpm) nₒ

nₒ = 10

The output sprocket has 10 teeth.  This makes sense, if the output sprocket is 4 times smaller, it will turn 4 times faster than the input sprocket.

Answer: it is 10 teeth and the guy under me already explained soo

Explanation:

Answer:

Apalancamiento.

Explanation:

El apalancamiento es el uso de dinero prestado (deuda) para aumentar el rendimiento esperado del capital. El apalancamiento se mide como la relación entre la deuda que devenga intereses y los activos totales. Cuanto mayor sea la deuda que devenga intereses, mayor será el apalancamiento financiero o "aceleración". Esto puede tener un efecto positivo o negativo.

Los costos por intereses de este capital de préstamo suelen ser fijos y se deducen de los ingresos. Un préstamo permite que una organización genere más ingresos sin un aumento necesario en el capital. Como no es necesario recaudar ni mantener capital social adicional, no se requieren pagos de dividendos adicionales (que no se pueden deducir de las ganancias). Sin embargo, un alto apalancamiento puede ser beneficioso durante los tiempos de auge, pero puede conducir a serios problemas de flujo de efectivo durante una recesión, ya que es posible que no haya suficientes retornos para cubrir mayores costos de intereses y obligaciones de reembolso.

Answer:

Explanation:

EFFECT OF INCREASING THE BOLIER PRESSURE ON

Answer:

You'd need to know things like the weight of the car, the spring constant of the suspension springs.

Explanation:

Driving over the curb slowly does not have much of an "impact" because of the small potential energy it has but to find the force that results from going over the curb at a much higher speed, you would need to know the weight of the car since it directly impact the force that it applies. You also would need to know about the car's suspension, the spring material, how stiff the springs are and their spring constant to calculate the force they absorb.

I hope this answer helps.

Answer: it spread by winds has a strong effect on fire behavior due to the fanning effect on the fire.Wind increases the supply of oxygen.

Explanation:

Fires need three things to occur in order to start and grow: oxygen, a spark/heat, and fuel. Wildfires in forests have plenty of fuel and heat is never really an issue, therefore the wind can cause a fire to continue and even spread faster. Wind will not only increase the fire's supply of oxygen, but it will   also blow the fire in many different directions, now causing the flames to spread.

Answer:

45

Explanation:

bdgdsfggsfg

Answer:

maximum roll-off factor is 0.7

Explanation:

given data

rate of output data  = 1,000,000 bits/sec

cutoff frequency fc = 850 kHz

solution

we know bandwidth frequency is same as that of bandwidth

we apply here fc formula that is

fc = ω ( 1 + α )     ..........1

here

ω = data rate ÷ 2   .............2

ω = 1000  ÷ 2  

ω = 500000 Hz

so put now value in eq 1

fc = ω ( 1 + α )

850000= 500000  ( 1 + α )

solve it we get

α = 0.7

so, maximum roll-off factor is 0.7

Answer:

A) 282.34 - j 12.08 Ω

B) 0.0266 + j 0.621 / unit

C)

A = 0.812 < 1.09° per unit

B =  164.6 < 85.42°Ω  

C =  2.061 * 10^-3 < 90.32° s

D =  0.812 < 1.09° per unit

Explanation:

Given data :

Z ( impedance ) = 0.03 i  + j 0.35 Ω/km

positive sequence shunt admittance ( Y ) = j4.4*10^-6 S/km

A) calculate Zc

Zc = [tex]\sqrt{\frac{z}{y} }[/tex]  =  [tex]\sqrt{\frac{0.03 i + j 0.35}{j4.4*10^-6 } }[/tex]    

    = [tex]\sqrt{79837.128< 4.899^o}[/tex]   =  282.6 < -2.45°

hence Zc = 282.34 - j 12.08 Ω

B) Calculate  gl

gl = [tex]\sqrt{zy} * d[/tex]  

 d = 500

 z = 0.03 i  + j 0.35

 y = j4.4*10^-6 S/km

gl =  [tex]\sqrt{0.03 i + j 0.35* j4.4*10^-6} * 500[/tex]

   = [tex]\sqrt{1.5456*10^{-6} < 175.1^0} * 500[/tex]

   = 0.622 < 87.55 °

gl = 0.0266 + j 0.621 / unit

C) exact ABCD parameters for this line

A = cos h (gl) . per unit  =  0.812 < 1.09° per unit ( as calculated )

B = Zc sin h (gl) Ω  = 164.6 < 85.42°Ω  ( as calculated )

C = 1/Zc  sin h (gl) s  =  2.061 * 10^-3 < 90.32° s ( as calculated )

D = cos h (gl) . per unit = 0.812 < 1.09° per unit ( as calculated )

where :  cos h (gl)  = [tex]\frac{e^{gl} + e^{-gl} }{2}[/tex]

             sin h (gl) = [tex]\frac{e^{gl}-e^{-gl} }{2}[/tex]

Answer: the reflection loss is 4%

Explanation:

Given that;

n for window glass is 1.5

we know that

Reflection Loss rλ = (nλ - 1)² / (nλ + 1)²

the reflection of loss rλ at normal incidence between two media with different refractive indexes rλ = n'/n, the ratio indices

where n is index of refraction of air ( 1 )

and n' is the refraction of window glass ( 1.5 )

our nλ is 1.5

so we substitute into the equation

rλ =[ (1.5 - 1)² / (1.5 + 1)²] × 100

= [0.25 / 6.25] × 100

= 0.04 × 100

= 4%

Therefore the reflection loss is 4%