X/-2=18 what is the solution to this equation?

What process is believed to be responsible for the formation of the grand canyon? a) diverging tectonic plates b) converging tectonic plates c) erosion over a long period of time d) caving in of the ground due to erosion

The biome pictured above is found in areas such as kenya and south africa. the land is grass-covered with very few trees and gazelles and other grazers are common here. why does this biome have a low population of trees? a) large grazing animals destroy the trees. b) it is a deforested rainforest with poor soil. c) it has high temperatures and low precipitation. d) it has a long rainy season followed by flooding.

98 points! include an answer and in advance!