What is A.s.t.c.?
Stands for "All Sluts Take Cock". An acronym for remembering the trignometric circle.
Billy: Sir, I don't remember which quadrants cosine is positive in.
Teacher: Remember A.S.T.C. - All Sluts Take Cock?
Billy: Ohh yeahhhh, quadrants 1 & 4!
See trig, atsc, circle, sine