question archive A 500 ft long spaceship with a mass of 8(10)^5 slugs is traveling at

Subject:PhysicsPrice: Bought3

A 500 ft long spaceship with a mass of 8(10)^5 slugs is traveling at .8 c towards a distant star system 4 light-years away. To a person on Earth the trip would take 5 years to reach the star system.

a) How long did the trip take as measured by someone on the spaceship?

b) To an outside observer what is the length of the spaceship as it travels pass them?