Please help i don't get it

Asmall foreign car gete 42 miles per gallon and user 35 gallons on a trip.gasoline costs $1.05 per gallon.what was the cost of gasoline per mile driver?

Identify a1 and r for the geometric sequence an= -256(-1/4) n-1

Your food costs are $5,500. your total food sales are $11,000. what percent of your food sales do the food costs represent?