Which word means nearly the opposite of contaminated

Why did many members of congress oppose president lincoln’s plan for reconstruction? a. they believed that freed blacks had gained too much power. b. they thought that the plan was too harsh on confederate sympathizers in the north. c. they thought that the president had overstepped his powers.

Eter lives in a beautiful region. peter and other residents of his region use water from the river that flows through their region. recently, mark industries decided to set up their chemical plant near that river. peter realized that the waste from the chemical plant would pollute the river. he decided to seek a legal ordinance that would restrict the use of land near that river for specific use only. which type of zoning will peter and his region?

Which environmental change allowed people to travel by land between asia and north america a. human apaption to arctic environments b. the introduction to horses to north america c. the formation of ice sheets on land d. a rise in ocean temperatures