Find each angle or arc measure 3,4,5,7, and 8

Beth took out a $20,000 loan for college she is borrowing money from two banks. bank a charges an interest rate of 8.5% bank b charges and interest rate of 10.5% after one year alice owes $1860 in interest how much money did she borrow from bank a

Can someone factor this fully? my friend and i have two different answers and i would like to know if either of them is right. you in advance. a^2 - b^2 + 25 + 10a

What is the geometric mean of 3 and 7? a) square root of 21 b) 2 square root of 6 c) 2 square root of 7 d) 21