Hi there!
We can use the work-energy theorem to solve.
Recall that:

The initial kinetic energy is 0 J because the crate begins from rest, so we can plug in the given values for mass and final velocity:

Now, we can define work:

Now, plug in the values:

Solve for theta:

Answer:
a) 
b) 
c) 
Explanation:
From the question we are told that
Distance to Betelgeuse 
Mass of Rocket 
Total Time in years traveled 
Total energy used by the United States in the year 2000 
Generally the equation of speed of rocket v mathematically given by


where




Therefore


b)
Generally the equation of the energy E required to attain prior speed mathematically given by


c)Generally the equation of the energy
required to accelerate the rocket mathematically given by



Answer: 0.5N
Explanation: if the system is at equilibrium, sum of the torque will be equal to zero.
But if they are not in equilibrium.
U will find the difference in the two torque
find the attached file for solution