Under her cell phone plan, violet pays a flat cost of $38 per month and $3 per gigabyte. she wants to keep her bill under $80 per month. which inequality can be used to determine xx, the maximum number of gigabytes violet can use while staying within her budget? a) 80>3x+38 b) 80>3(38+x) c) 80<3x+38 d) 80<3(38+x)