Which of the following represents the prime factorization of 23? 1 · 3 · 8
1 · 2 · 2 · 2 · 3
1 · 2 · 3 · 4
1 · 23

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?