Why does water frozen in the cracks of a rock to break down the rock?

Find the coordinates of a if b(-9,-10) is the midpoint of ac and c has the coordinates of (-1,9)

Advantages and disadvantages of mitigation and adaptation

What statement about charlemagne is not true? a. charlemagne's empire collapsed during his rule b. charlemagne sent missionaries throughout europe c. charlemagne encouraged the arts and education d. charlemagne ruled much of western europe a. charlemagne's empire collapsed during his rule