Saturn orbits the Sun at a radius of about 1.4×109 km. At this distance the force of gravity on Saturn due to the Sun is 3.7×1022 N. Assuming Saturn's orbit to be perfectly circular, how much work grav does the Sun's gravity do on Saturn in one year?

Samir watches a 100-minute movie on his spaceship. maria's spaceshipe flies in the same direction as samir's spaceship but she observes his move to last 125 minutes and his spaceship to be 40 m long. how long does samir observe his own spaceship to be? according to an observer on earth, planet x is stationary. maria and samir depart earth on their spaceships at the same time, each flying at 0.5c. maria flies toward planet x and samir flies in the opposite direction. according to maria, her voyage to planet x takes 9 years. how many years does marias voyage take according to samir?