Explanation:
Given that,
Terminal voltage = 3.200 V
Internal resistance 
(a). We need to calculate the current
Using rule of loop


Where, E = emf
R = resistance
r = internal resistance
Put the value into the formula


(b). We need to calculate the terminal voltage
Using formula of terminal voltage

Where, V = terminal voltage
I = current
r = internal resistance
Put the value into the formula


(c). We need to calculate the ratio of the terminal voltage of voltmeter equal to emf


Hence, This is the required solution.
Answer:
Maximum height reached by the rocket is

total time of the motion of rocket is given as

Explanation:
Initial speed of the rocket is given as

acceleration of the rocket is given as

engine stops at height h = 150 m
so the final speed of the rocket at this height is given as



so maximum height reached by the rocket is given as the height where its final speed becomes zero
so we will have



Now the total time of the motion of rocket is given as
1) time to reach the height of 150 m



2) time to reach ground from this height



so total time of the motion of rocket is given as

The force applied to an object is said to be a product of its mass and the acceleration. For this case, acceleration is the reading on the gravitometer. We calculate as follows:
F = mg
39.36 N = m(9.83 m/s^2)
m = 4.00 kg
Hope this answers the question. Have a nice day.