In which theater was Abraham Lincoln shot in 1865?

Which president was never elected as either president or vice president? Which president pardoned Richard Nixon? Which four presidents were assassinated in office? Who assassinated Abraham Lincoln? In which city was John F. Kennedy assassinated in 1963? Who was accused of assassinating John F. Kennedy? Which president survived an assassination attempt by John Hinckley Jr. in 1981? Which presidents have been impeached by the House of Representatives?