A starship voyages to a distant planet 10 ly away. The explorers stay 4.00yr , return at the same speed, and arrive back on earth 26 yr after they left. Assume that the time needed to accelerate and decelerate is negligible.
(a) What is the speed of the starship?
_______*c
(b) How much time has elapsed on the astronauts' chronometers?
_______years