1. You stop at a self-service gas station to buy 15 gallons of 87-octane gasoline at $2.22 per gallon. The gas pump is accurate to within 1/10 gallon. How much might you be undercharged or overcharged?

2. The side length of a square is 10.4-inches with a possible error of 1/16 inch. Determine the interval containing the possible areas of the square.

3. The side length of a square is 24.2-centimeters with a possible error of 0.25 centimeter. Determine the interval containing the possible areas of the square.