• Assume you can buy 20 pounds of propane for $14.00. 
• Consider whether you will leave the driveway wet or dry.
• The heat of fusion of water is 6.0 kJ mol^-1.
• The heat of vaporization of water is 40.7 kJ mol^-1. 
• The specific heat of water is 4.18 J g^-1 °C^-1.
• The heat of combustion of propane is –2220 kJ mol^-1.

How much will you have to charge your customers in order to make a profit?

You may use these estimates:

• Average driveway is 1000 ft²
• Average snowfall is 6 inches.
• 12 inches of snowfall is equivalent to 1 inch of rainfall.

(For simplification, you may neglect labor costs, and ignore safety consideration for now.)