physics . . . help please?

Question

A hair dryer draws 7.5A when plugged into a120-V line.

A) What is it's resistance?

B) How much charge passes through it in 15 min?

(assume direct current)

Please show work, so I can understand how to solve similar problems.

Answer 1

The answer above is correct for a) but is 16 ohms.
b) is easy: charge = Coulombs = amps x time (in seconds) = 7.5A x 15(60) = 6750 Coulombs

Answer 2

V = IR, so
120 = 7.5 R R=16 amps

I forget the conversion between amps and electrons/time, sorry.