Question

the text below describes how an areas environment changed over time. read the text. then answer the question.
a fast - flowing river deposited heavy sediment grains along its banks. light sediment such as mud was carried away by the strong water current.
sediment deposited by a fast - flowing river
over thousands of years, the river dried up, and the area became a desert. in the desert, sediment was deposited by wind.
sediment deposited in a desert
how did the sediment deposited in this area change over time?
first, a layer of sand was deposited. later, a layer of sand and pebbles was deposited.
first, a layer of sand and pebbles was deposited. later, a layer of sand was deposited.

Explanation:

The first situation is a fast - flowing river depositing heavy sediment (pebbles) and carrying away light sediment (mud). So the first deposit is heavy sediment (pebbles and maybe some sand - like heavier particles compared to mud). Then the area becomes a desert where wind deposits sediment. Wind - deposited sediment is usually fine sand.

Answer:

First, a layer of sand and pebbles was deposited. Later, a layer of sand was deposited.