Under his cell phone plan, Robert pays a flat cost of $67 per month and $4 per gigabyte. He wants to keep his bill under $80 per month. Which inequality can be used to determine gg, the maximum number of gigabytes Robert can use while staying within his budget? 4(67+g)<80 4(67+g)<80 4(67+g)>80 4(67+g)>80 80>67+4g 80>67+4g 80<67+4g80<67+4g