The 1968 Tet Offensive was a turning point in which war?

In which 1968 film does Steve McQueen play a San Francisco cop hunting the mobsters who killed a witness? Taylor, Cornelius and Dr. Zaius are characters in which 1968 film? Which author's "The Armies of the Night" won both a Pulitzer Prize and the National Book Award in 1969? In which 1968 horror film does a young wife come to suspect that her baby's father is Satan? Which casino with a double name opened in Las Vegas in 1968 as one of the first to cater to families? Which figure skater won the only U.S. gold medal at the 1968 Winter Olympics in Grenoble? Which country's epic film "War and Peace" won the Oscar for Best Foreign Language Film for 1968? Who joked "Welcome to the Academy Awards, or as it's known at my house, Passover"?