8× 10−6 is between which two numbers? 1 x 10-7 and 1 x 10-8 1 x 10-4 and 1 x 10-5 1 x 10-6 and 1 x 10-7 1 x 10-5 and 1 x 10-6

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?