Please help. The diagram below shows four layers of Earth. Which of these layers is composed of materials with a plastic nature?
Layer A
Layer B
Layer C
Layer D

During which era in earth's history were the first insects? mesozoic precambrian cenozoic paleozoic

Zac wanted to determine the measure of r and of ? r in the triangle below. to fine the measure of r, zac sets up the problem.42^2 + 24^2 = r 2. determine whether zac set the problem up correctly.

Put these ecosystems in order of least biodiversity to most biodiversity 1. mediterranean forest 2. indonesian rain forest 3. arctic ocean