Question

PLEASE HELP!! 20 POINTS!

Answer 1

It's something to do with the weathering process. Eg. At night it's really cold, and in the day it's really hot. Because the temperature keeps changing dramatically day in and day out, the sand dunes start to be sort of hacked or re-shaped, or even formed.

Answer 2

Hi there!

This "phenomenon" happens because of erosion caused by wind and deposition. Wind picks up grains of sand and deposits it when the sand encounters an obstacle (in this case, a sand dune or the like). Because the sand is not held in place like soil, the dunes are constantly changing, allowing for varied shapes and sizes of the dunes every year Eli and his family visit.

I hope that helps you out! Have a great day! :)