3 GBs per month because you have to take 30-21 (the monthly cost of the phone)=9 and each GB is $3 a month so 9 divided by 3= 3
B) c - 1/5c - 40 = 120
c- (original cost) - 1/5c (sale) - 40(coupon)= 120(final cost)
Hope that helps! :)
Answer: Check explanation
Step-by-step explanation: -g-6, 9d+3, -12y+20, 14n-29, -2c, x+21/2