Al-ounce letter costs $0.50 to mail through the postal service. A 3-ounce letter costs $0.92 to mail through the postal service.
The postal services calculates the weight to the whole ounce.
What functions represent the total cost f (x) to send a letter that is 2 ounces? Select all that apply.

A:f(3) = 0.21 (x - 1) + 0.50

B:f(x) = 0.50 (2 – 1) + 0.21

C: f(x) = 0.50x

D:f(3) = 0.213 +0.29

E:f(1) = 0.212