Find the mean of the following data set: (Round to the nearest 10th) 2,3,10,15,20,24,30

This is geometry. could anyone ? i can't fail this class. my grade is quite low already.

Alex drew a circle with right triangle prq inscribed in it, as shown below: the figure shows a circle with points p, q, and r on it forming an inscribed triangle. side pq is a chord through the center and angle r is a right angle. arc qr measures 80 degrees.

If tan2a=cot(a+60), find the value of a, where 2a is an acute angle