Aroller coaster with a potential energy of 235,200 j sits at the top of a 30 m high hill. what is the mass of the roller coaster? (formula: pe = mgh) 800 kg 7,840 kg 8,000 kg 78,400 kg

Jet streams are relatively narrow bands of strong wind in the upper levels of the atmosphere. the winds blow from west to east in jet streams but the flow often shifts to the north and south. jet streams follow the boundaries between hot and cold air. the earth's rotation is responsible for the jet stream as well.

The speed was not exceeded so it was slow