Annabelle is taking the polar express all the way to the north pole! the polar express is 100 meters long and it takes 30 seconds to cross santa’s 400m ice bridge. what speed is the train going at? (30,45,60,80km/h)

Agroup of students were investigating the force of gravity. they began by dropping a foam ball from a height of 3 meters into a bucket of sand. the ball hit the sand in 0.306 seconds. they dropped additional balls of approximately the same diameter, but of different masses. here is the data they collected. based on this experiment and the collected data, what would their conclusion be?