In a destructive wave,

backwash is stronger than swash
swash is stronger than backwash
water hits the beach in a straight line
sand and small rocks are deposited by water

A. Backwash is stronger than swash

Explanation:

"Destructive waves" are usually found in more exposed bays. They build "pebble beaches". Although a destructive wave’s swash is much stronger than that of a constructive wave. But the "swash" of destructive waves is weaker than the "backwash". This means that these waves can transport beach material back into the sea. Hence in the winters, the heights of the beaches are comparatively lower. These waves destroy the beaches. They usually have high waves, but short wavelength and are very frequent.

b. 20: 5

explanation:

20% of the worlds population lives in southwest asia, and less than 5% of the world's

land area.