Role of vegetation in mechanical weathering

Mechanical weathering occurs when roots grow and cause the rock to break (just like the roots that crack the sidewalk). Chemical weathering occurs when roots release chemicals, like acid, which then break down the rocks. Plants can cause both mechanical and chemical weathering.

when in doubt choose c

it's what my teacher told my class when we were going into psats

although the crusades failed to capture jerusalem, they had several major impacts on western europe. they increased the authority of the king: sometimes nobles died in battle without leaving an heir in which case the king got their land. kings passed taxes to pay for the crusades.