The Basketmaker I people a.
are assumed to exist, but there is very little evidence.
b.
lived in large groups.
c.
were farmers and used irrigation.
d.
built stone houses.

C

Explanation:

The Basketmaker people were farmers and used irrigation

doesn't make any since

explanation:

- three-quarters or two-thirds..

- "the constitution provides that an amendment may be proposed either by the congress with a two-thirds majority vote in both the house of representatives and the senate or by a constitutional convention called for by two-thirds of the state legislatures."

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