3 What is compression?
А
When alr molecules move apart from one another.
B
When alr molecules collide with one another.
C
When alr molecules become packed tightly together.
D
When alr molecules move around freely.

the mantle

explanation:

earth is divided into three layers: the crust or the outermost layer on which we live; the underlying, middle layer - the mantle - and the core (the innermost layer of earth).

o conteúdo de calor de um sistema é igual à entalpia apenas para um sistema que é constante

the correct answer would be b. amelia, because the particals of gas move really fast (charged particals) and gas also has a lot of room (particals move independently) so the only answer that has both of those is amelia's.