Changing steep slope into usable land is called:

Terracing

Explanation:

Terracing is mostly used in agriculture, it is a practice of converting slopes for useful farm practices like farming and this also helps to prevent erosion by reducing the water velocity.

It is an ancient agricultural practice, where mountainous landscapes are converted to platforms.

all fossil fuels are nonrenewable, so think coal, gasoline, things that we will eventually run out of. all fossil fuels are nonrenewable resources, but not all nonrenewable recourses are fossil fuels. these resources are not being renewed as fast as we are using them. i hope this considering there weren't any answer choices.