Suppose you were a citizen of America 2, a country on the planet Earth 2 in an alternate universe where everything is the same except the speed of light is 100 km/hr. Let's say you get in your car in the east coast, drive across the country (4800 km in the Earth 2 frame) at 60 km/hr w.r.t. Earth 2 and stop on the west coast. How much younger are you after this trip relative to your twin who stood still w.r.t. Earth 2 during the trip?

A. 5 hours B. 20 hours C. 16 hours D. You are not younger your twin is younger

A ship travels at speed 3c/5 relative to earth and lands on a star. Neglect effects due to acceleration/deceleration. On earth 5 years have passed, so an earth observer sees the ship has aged 4 years. At the end of its voyage, how much time does the ship observer see has passed on earth?

A. 5 years B. 6.25 years C. 3.2 years D. You cannot determine from the given information