How to evaluate these?

Evaluate the following expressions. Your answer must be an angle 1r/2 S 0 S 71' in radians. Give exact answers; do not use decimal answers. You can enter the number 7r as pi. E.g. if the answer is 7r/ 2 you could enter pi/2 or 1/2*pi. sin-1p?) = i, sin1(1): a; cos1(l)= f, cos1(%)= f