Me with this problem ive been on it for 3 days now!

lucy wants to be exempt from her semester exam. in order for that to happen, she has to average an 85 over 3 test grades. her first 2 test grades were 81 and 86. what does lucy need to make on her third test in order to have an exact average of 85 and be exempt from her exam?

Frank has $66.50 in his account on sunday. over the next week, he makes the following changes to his balance via deposits and purchases: day debit ($) credit ($) monday 60.33 80.75 tuesday 54.45 wednesday 49.20 15.00 thursday 35.40 friday 16.85 75.00 saturday 80.56 on what day does frank first get charged an overdraft fee? a. wednesday b. thursday c. friday d. saturday select the best answer from the choices provided a b c d

Compare these two waves: the blue and orange waves have the same pitch, but the blue wave is louder. the blue and orange waves have the same volume, but the blue wave has a higher pitch. the orange wave has a higher pitch, but the blue wave is louder. the blue wave has a higher pitch, but the orange wave is louder.

Find the zeros of each function. f(x) = 6x^2 - 7x - 20