(a) Let's convert the final speed of the car in m/s:

The kinetic energy of the car at t=19 s is

(b) The average power delivered by the engine of the car during the 19 s is equal to the work done by the engine divided by the time interval:

But the work done is equal to the increase in kinetic energy of the car, and since its initial kinetic energy is zero (because the car starts from rest), this translates into

(c) The instantaneous power is given by

where F is the force exerted by the engine, equal to F=ma.
So we need to find the acceleration first:

And the problem says this acceleration is constant during the motion, so now we can calculate the instantaneous power at t=19 s:
Ariana Grandeeeeeeeeeeeeeeeeeeeeeee
Using Newton's Second Law, F = ma, where F is the net force
So the net force is:
F = (6kg)(4m/s^2) = 24N
Since you are applying a horizontal force of 30N, we can find the force of friction by the difference of the net force and the applied force.
30N-24N = 6N
The volume of the block of wood is given by length × width ×height
= 2.75 × 4.80 × 7.5
= 99 cm³
Density is given by mass/volume
Thus = 84.0 g/ 99 cm³
= 0.848 g/cm³
Hence; since the block is less dense than water (1 g/cm³) it will float
Jeremy’s son has more mass, so it would take more forever to reach the same height as his daughter