Help who ever gets right gets brainliest

If 30 lb of rice and 30 lb of potatoes cost ? $27.60? , and 20 lb of rice and 12 lb of potatoes cost ? $15.04? , how much will 10 lb of rice and 50 lb of potatoes? cost?

Sara made $253 for 11 hours of work. at the same rate how much would he make for 7 hours of work?

Which unit rate is the lowest price per ounce? (5 points) choice a: 6 ounces of chocolate chips for $2.49 choice b: 8 ounces of chocolate chips for $3.32