Energy remains constant, so it doesn't change, which means it is conserved. The answer is a, the law of energy conservation.
Inclined Component of the bicyclist's velocity:
Vi = 500/10 = 50 m/s
Vertical Component of the bicyclist's velocity:
(This is simply the cosine of the Vc)
Vv = 50Sin30 = 25 m/s
The vertical velocity is 25 meters per second.
There is no sound in space because there is no medium to move it. However i think the big bang can still been seen in the form of background radiation but i am unsure.
It has 178200000 ms^-1 and the train has 25200000ms^-1.