A gas station is charging $1.299 per gallon of gas. what would be the price for a liter of gas?

You can transform gallons into liters and you have that ##1 gallon=3.785 liters## so in 1 gallon (that costs 1.299 $) you have 3.785 liters. You now divide the price (of 1 gallon) by the number of liters you have in 1 gallon and you get the price per liter:
##1.299/3.785## $/liters##=0.343## $/liter.
The swimmer swims 85.4 yards=78.1 meters in 5 minutes that are (1 minute = 60 seconds) ##5*60=300## seconds; so he swims ##78.1/300=0.26## meters in 1 second; in 70 seconds he’ll swim:
##0.26*70=18.22##m.