In an attempt to reduce the extraordinarily long travel times for voyaging to distant stars, some people have suggested traveling at close to the speed of light. Suppose you wish to visit the red giant star Betelgeuse, which is 430 ly away, and that you want your 20,000 kg rocket to move so fast that you age only 20 years during the round trip. A. How fast (v) must the rocket travel relative to earth?
0.99973 c

B. How much energy is needed to accelerate the rocket to this speed?

C. How many times larger is this energy than the total energy used by the United States in the year 2000, which was roughly 1.0×1020J?

I need help with B and C. For B, I keep getting 0 which is not correct and I don't know what I am doing wrong. C relies on my answer for B, so if I get B wrong then C is wrong as well. Thanks!