What does a marine fossil in a desert tell scientists? A. The desert was always a desert.

B. The area was once under water.

C. Marine life once lived on land.

D. Marine fossils cannot be found in a desert.

Drag and drop a statement or reason to each box to complete the proof. statement reason △abc , de⎯⎯⎯⎯⎯∥ac⎯⎯⎯⎯⎯ given corresponding angles postulate △bde∼△bac babd=bcbe polygon similarity postulate ba=bd+dabc=be+ec bd+dabd=be+ecbe substitution property of equality bdbd+dabd=bebe+ecbe addition of fractions 1+dabd=1+ecbe simplify. dabd=ecbe subtraction property of equality

Suggest two reasons why irrigation is important for human development of the desert (4 marks)

What is the thickest layer of earth called?