How many one-to-one correspondences exist between A = {1, 2, 3, 4} and B = {a, b, c, d, e}

Which of the following properties can be used to show

1foot = 12 inches; 1 yard = 3 feet

Jalen charges $25.50 for every 3 hours of yard work he does for his neighbors. ralph charges $34 for every 4 hours of work that he does. who charges less? opinions: 1.they charge the same amount 2.jalen 3.ralph