Who signed a treaty with President Washington to give up some Creek lands?

William McIntosh

Explanation:

The Lower Creek Council, a small faction led by Troup's first cousin, William McIntosh, signed the Treaty of Indian Springs on February 13, 1825, ceding a large amount of Creek territory to the United States.

Choctaw American Indian tribe

Explanation:

The Treaty of Dancing Rabbit Creek was a treaty signed on September 27, 1830, and proclaimed on February 24, 1831, between the Choctaw American Indian tribe and the United States Government. This was the first removal treaty carried into effect under the Indian Removal Act.

the answer to your question is a. the salt plains

in 1811, he led an expedition, known as the george c. sibley expedition, to improve relations with the pawnee and kansa tribes, and also to locate the rumored jefferson's salt mountain