Mary's diet is to contain at least 24 units of carbohydrates and 19 units of protein. Food substance A costs $1.40 per unit and each unit contains 3 units of carbohydrates and 4 units of protein. Food substance B costs $0.80 per
unit and each unit contains 2 units of carbohydrates and 1 unit of protein. How many units of each substance
should she purchase in order to minimize cost? What is the minimum cost?

Gigi earned $65 for 5 hours of gardening. she earned $90 for 9 hours of office work. which statement correctly compares gigi’s earning per hour for gardening and office work? she earned $3 more per hour for office work than for gardening. she earned $4 more per hour for office work than for gardening. she earned $3 more per hour for gardening than for office work. she earned $4 more per hour for gardening than for office work.