Can someone help PLS

Which of the following domains provide a real value periods

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?

Me asap the graph shows the relationship between the price of frozen yogurt and the number of ounces of frozen yogurt sold at different stores and restaurants according to the line of best fit about how many ounces of frozen yogurt can someone purchase for $5? 1 cost of frozen yogurt 1.5 2 13 15.5 cost (5) no 2 4 6 8 10 12 14 16 18 20 size (oz)