Why would ships or trains be a better choice than airplanes for moving wheat

What was the first instrument to ever record an earthquake?

Hunter is in lab. he clears a spot on his lab bench to start working. he also puts his lab coat and goggles on. he then identifies where all of the safety equipment is. he notices his station is next to the fume hood, which ventilates the chemicals stored there. the noise of the fume hood was bothersome, so hunter turned it off. which could be an error in his set-up? he should not turn off the fume hood.  he should wait to put on his coat until after the directions are given.  he should wait to put on his goggles until after the directions are given.  he should not sit next to the fume hood. 

The momentum of a man riding his bicycle downhill can be calculated. the bicycle and the man have a combined mass of 40 kg. the velocity of the bicycle is 10 m/s. calculate the momentum.