ORANGE CITY, Iowa (AP) — Northwestern College says it’s received a $6 million gift for its new science building, the largest single gift in school history. The $24.5 million building will be named for benefactors Jack and Mary DeWitt, who live in Holland, Michigan. The building will have classrooms, laboratories and faculty offices for the college’s biology, chemistry and nursing department, as well as space for student-faculty research. It is scheduled to open in August. Jack DeWitt served on the college board of trustees for 13 years.