HELP :)

What is the compound interest in a three-year, $100,000 loan at a 10 percent annual interest rate a) 10.00 b) 21.00 c) 33.10 d) 46.41

Astore sells two types of radios. one type sells $87 and the other for $119. if 25 were sold and the sales were $2495, how many of the $87 radios were sold a) 5 b) 20 c) 15 d)10

Will mark ! (10 points also! ) if x varies inversely with y and x =6 when y= 10, find y when x=8 a. y=4.8 b. y=7.5 c. y=40/3 d. y=4/15