A friend gave me these questions to answer. "A certain star is 7.0 light years away. How long would it take a spacecraft traveling at .950c to reach that star from Earth, as measured by observers (a ) on earth (b )on the aircraft (c ) what is the distance travled according tio observers on the spacecraft? (d ) what will the spacecraft occupants compute their speed to be from the results of (b ) and (c )?" I fear taking the obviouse path, for it may take me to answer which contradicts that which you would get if you applied the lorentz transformations, which I know nothing of. What would be the correct way of going about this question? and this was the second question. "Derive the general relativist equation of T = To sr (1 - v^2/c^2)" I have no idea of how to go solving about this one.