i need help with the question. the question is (look at this set of ordered pairs: 20, 1 16, -6 13, 12 13, 16, is this relation a function? yes or no?​

Becca wants to mix fruit juice and soda to make a punch. she can buy fruit juice for $3 a gallon and soda for $4 a gallon. if she wants to make 28 gallons of punch at a cost of $3.25 a gallon, how many gallons of fruit juice and how many gallons of soda should she buy?