As you get higher the atmospheric pressure lowers. The pressure in the packet of crisps has the pressure at which it has been closed (pressure at the surface of the earth). This means that the air molecules in the packet press harder outside than the air molecules in the atmosphere press on the packet.
I do not know i am doing this for the points
Ok number one is A number 2 is C number 3 is A number 4 is B hope it helps
A deep-sea diver must descend and ascend in short steps to equalize pressure on his body.
