What best describes the mantle of Earth?
A: the largest layer between the crust and outer core

Some students were on a tour exploring the inside of a cave. While the students were in the cave, they realized they heard an echo every time that they spoke. Which most likely caused the echo to occur?
A: the reflection of the sound waves

Scientists dig in a dry area at the bottom of a mountain range. Fossilized shells of freshwater mussels are found in the area. Which is a likely conclusion that scientists will draw based on this evidence?
A: Rivers once flowed through the area.

Increased populations can lead to the depletion of locally available resources. Compared to other communities, which of these locally available resources is most likely to be depleted in desert communities?
A:
water