Please help me with number 1

Answer:
-⅘
Step-by-step explanation:
Take cos⁻¹ -⅘ to get your x-value of -2,498091545 [radians], then plug it into the sine function to get this:
-sin(-2,498091545 + π\2) ≈ -⅘
↑
This negative is on the outside according to the Trigonometric Identity rules, and that it lies in Quadrant III.
I hope this is the correct answer, and as always, I am joyous to assist anyone at any time.