When getting off the elevator on the fourth floor, if you make a right, you will run into restrooms, as well as a staircase. Around the corner on your left-hand side are offices 401A-R. on the right-hand side are classrooms 417, group study rooms 405 B-D, room 405A, classroom 416, 415, staircase, room 413, 414, and offices 411 H-A.