Easy math multiple choice

Suppose a pendulum is l meters long. the time, t,in seconds that it tales to swing back and forth once is given by t=2.01

Solve the equation using the zero-product property. -3n(7n - 5) = 0 a. 0, -5/7 b. -1/3, -5/7 c. -1/3, 5/7 d. 0, 5/7

Emily is entering a bicycle race for charity. her mother pledges $0.90 for every 0.75 mile she bikes. if emily bikes 18 miles, how much will her mother donate?