Does 5.2 belong with irrational or rational numbers?

Don't know how to find x given these segment lengths

Check all that apply. f is a function. f is a one-to-one function. c is a function. c is a one-to-one function.

At the beginning of the year, adrian's savings account balance was \$28$28. each week, he deposits another \$15$15 into that account, and he doesn't spend any of his savings. is his savings account balance proportional to the number of weeks since the start of the year?