(2a^3b^-2)(-4a^2b^4) assume that no variable equals 0

Bob’s bank charges him a $3.15 service fee every time he uses an out-of-network atm. if bob uses an out-of-network atm an average of three times every two weeks, how much will he pay in service fees over the course of a year? a. $327.60 b. $109.20 c. $491.40 d. $245.70 select the best answer from the choices provided a b c d

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