Help a brother out lol

Find the length of the following tangent segments to the circles centered at o and o' whose radii are 5 and 3 respectively and the distance between o and o' is 12. what is the tangent segment of cd?

List the sides of δrst in in ascending order (shortest to longest) if: a ∠r =x+28°, m∠s = 2x+16°, and m∠t = x+12°

Dakota earned $7.50 in interest in account a and $18.75 in interest in account b after 15 months. if the simple interest rate is 4% for account a and 5% for account b, which account has the greater principal? explain. to make it a little easier, there is an image. good luck!