A gas consists of 1024 molecules, each with mass 3 × 10-26 kg. It is heated to a temperature of 300 K, while the volume is held constant. 1) If the gas is confined to a vertical tube 7 × 103 m high, what is the ratio of the pressure at the top to the pressure at the bottom?

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 maria's voyage take according to samir?