Most of the earth's volume is contained in the
a. mantle
b.
crust
c.
inner core
d.
outer core

Its A

Explanation:

This region is known as the mantle, and accounts for the vast majority of the Earth's volume. Movement, or convection, in this layer is also responsible for all of Earth's volcanic and seismic activity

i am pretty sure it is c because when people are closer together, they cannot move as freely. picture being in a mostly full elevator, for instance. the people are right next to you, and you can barely move.

answer; equivalent to a one(1) horsepower motor;