Why is sand used in sand replacement method?​

The sand replacement test method is also used to determine the in-place density of compacted soil in order to compare it with the designated compaction degree, hence it specifies how much the compaction of the soil is close to the designated compaction degree.

Explanation:

answer; in the united states the plains include the great plains of the west and the tail grass prairie to the south of the great lakes extending east to the appalachian plateau