please help me out here.

3. Find the exact value of each of the following. Do not use a calculator answers given as decimals will not receive credit. If}: A. cos[] Part I: Find two common angles that either add up to or differ by 13. Rewrite this problem as the cosine of either a sum or a difference of those two angles. (2 points) \f17;: B. lan[12 ] Part I: 1?)! Find two common angles that either add up to or differ by 7' Rewrite this problem as the tangent of either a sum or a difference of those two angles. (2 points) Part II: Evaluate the expression.(4 points) C. sin(195') Part I: Find two common angles that either add up to or differ by 195. Rewrite this problem as the sine of either a sum or a difference of those two angles. (2 points) Part II: Evaluate the expression.(4 points) D. cot(15') Part I: Find two common angles that differ by 15. Rewrite this problem as the cotangent of a difference of those two angles.(2 points) Part II: Evaluate the expression.(4 points)