Magnitude of acceleration = (change in speed) / (time for the change) .
Change in speed = (ending speed) - (starting speed)
= zero - (43 m/s)
= -43 m/s .
Magnitude of acceleration = (-43 m/sec) / (0.28 sec)
= (-43 / 0.28) (m/sec) / sec
= 153.57... m/s²
= 1.5... x 10² m/s² .
You have three known variables:
Acceleration -

Time -

Initial Velocity -

For the first part of your question:

For the second part of your question:

This still needs to be converted to m/h:
Answer:
The drag coefficient is
Explanation:
From the question we are told that
The density of air is 
The diameter of bottom part is
The power trend-line equation is mathematically represented as

let assume that the velocity is 20 m/s
Then


The drag coefficient is mathematically represented as

Where
is the drag force
is the density of the fluid
is the flow velocity
A is the area which mathematically evaluated as

substituting values


Then

We know V=IR (Ohm's law).
We are given R=180Ω and I=0.1A, then V=(0.1AΩ)(180Ω). Therefore
V=18V