Ok good , I'll start
1.- Sin O = opposite side / hypotenuse
We have sin0 = -12/13
2.- We get the value
[tex]\sin ^{-1}\text{ }\theta\text{ = 67.38}[/tex]
In the third quadrangle
0 = 180 + 67.38
0 = 247.38° This is the result
28.- cos 0 = 1/3
[tex]\cos ^{-1}0\text{ = 0.333333 = 70.53\degree}[/tex]
In the fourth quadrangle
0 = 360 - 70.53
0 = 289.47°
