If you heat that air by 100 degrees F, it weighs about 7 grams less. Therefore, each cubic foot of air contained in a hot air balloon can lift about 7 grams. That's not much, and this is why hot air balloons are so huge -- to lift 1,000 pounds, you need about 65,000 cubic feet of hot air.
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



Pounds
If you are talking about the unit of measurement for weight is that of force it would be Newtons.
I hope I am correct my Science teacher said this was the answer to your question