1. find the sum. (4n2 + 2n + 8) + (5n2 + n + 13)
a. 9n2 + 3n + 21
b. 9n4 + 3n2 + 21
c. 9n2 + 2n + 21
2. find the sum. (2x2 - 5x + 2) + (x2 - 2x + 5)
a. 3x2 - 7x + 7
b. 3x2 - 3x + 7
c. 2x2 + 3x + 7

6n^2-7n-75=0 solve by quadratic formula

Roger and natalie travel in similar cars. roger's car drives the two miles to school in 7.5 minutes. natalie drives the same distance in the opposite direction but in only 6.5 minutes. what is true of their velocities?

Awater holding tank measures 105 m long, 50 m wide, and 8 m deep. traces of mercury have been found in the tank, with a concen- tration of 60 mg/l. what is the total mass of mercury in the tank? answer in units of kg.