The first law is about force or push and pull
Answer:
A
Explanation:
Let the x represent the amount of heat generated from the fossil fuel.
88% of x = 0.88 x
0.88 x was used to convert water to steam.
heat carried by steam = 40% × 0.88 x = 0.352 x
efficiency of the heat -to- work conversion = work output / work input = 0.352 x / x = 0.352 × 100 = 35.2 % which is less than 40 %
When acceleration is constant, the average velocity is given by

where
and
are the final and initial velocities, respectively. By definition, we also have that the average velocity is given by

where
are the final/initial displacements, and
are the final/initial times, respectively.
Take the car's starting position to be at
. Then

So we have

You also could have first found the acceleration using the equation

then solve for
via

but that would have involved a bit more work, and it turns out we didn't need to know the precise value of
anyway.