Is it ensure, insure, or assure?
city, Berkshire county, western Massachusetts, U.S. It lies on the headstreams of the Housatonic River, in the Berkshire Hills, 55 miles (88 km) northwest of Springfield. Settled in 1752 as the Pontoosuc Plantation, it was incorporated as a town (and made the county seat) in 1761 and named for the English prime minister William Pitt. It developed from a farming to an industrial community during the early 19th century because of abundant waterpower. Pittsfield now has a diversified economy; a wide variety of plastics are produced, and health care, business services, and the insurance business are also prominent