Which sentence is correctly punctuated? The observatory theater has three weekday showings, 11:00 a.M., 1:00 p.M., and 3:00 p.M. The observatory theater has three weekday showings: 11.00 a.M., 1.00 p.M., and 3.00 p.M. The observatory theater has three weekday showings—11:00 a.M., 1:00 p.M., and 3:00 p.M. The observatory theater has three weekday showings—11.00 a.M., 1.00 p.M., and 3.00 p.M.