If XY=30 , XZ=24, and JQ=8 , find the radius of the circumscribed circle of XYZ.

Really need on these. i have no idea what to do

What values of c and d make the equation true?

Determine the common ratio and find the next three terms of the geometric sequence. 10, 2, 0.4, a. 0.2; -0.4, -2, -10 c. 0.02; 0.08, 0.016, 0.0032 b. 0.02; -0.4, -2, -10 d. 0.2; 0.08, 0.016, 0.0032 select the best answer from the choices provided a b c d