Find the reference number for each value of t.
(A) t=9pi
(B) t= -5pi/4
(C) t=37pi/6
(D) t=4

(A) For ( t = 9π ): The reference angle is \( π \).
(B) For ( t = -5π ÷ 4 ): The reference angle is 1 ÷ 4π
(C) For t = 37π ÷ 6 The reference angle is 1÷6π.
(D) For \( t = 4 \): The reference angle is 0