I'm guessing what questions 1.3.1-1.3.3 are: for 0°<θ<90°:
1.3.1) sinθ=0.2524; Answer: θ=14.62°
1.3.2) cos(3θ-14°)=cos(52°); 3θ-14=52, 3θ=66°; Answer: θ=22°
1.3.3)
a) tan(2θ)=4, answer: 2θ=75.96°; answer: θ=37.98°; or:
b) tan2θ=4, tanθ=2, answer: θ=63.43°.
1.3.4) ?