When shopping for a new window-unit air conditioner for your home, understand that not just any size works for any room of the house. If you install too large an air conditioner, yes, it will cool a room very quickly. But air conditioners do two things: They remove heat and humidity from the air. If it cools too quickly, it removes the heat but leave the excess moisture, making it feel very cold and damp. To choose the right unit, measure the room you want to cool and search "air conditioner cooling needs calculator" to find an online tool to help you choose the right size unit. And as always, look for Energy Star-rated models to save the most energy to stay cool this summer.

Almost all gasoline today includes the additive ethanol, which is added to fuel to oxygenate it and reduce air pollution. When choosing gasoline at the pump, you may be given a choice between gasoline rated E10 (which is 10 percent ethanol) and E15 (15 percent ethanol). To protect your car, Popular Mechanics suggests avoiding gas rated E15 if your car was manufactured before 2001. Ethanol is an alcohol, and it can be corrosive to rubber and certain metals, and many vital parts of cars are made from those materials. Cars made after 2007 are compatible with the E15 blend because automakers adapted the newer cars for the higher grade of ethanol gas.

Planning to take a road trip this summer? While it may seem kinder to the planet to roll down the windows when driving at fast speeds on the highway, it's actually a fuel-efficiency nightmare. Opening windows or the sunroof reduces the car's aerodynamic design, creating drag and lowering your average miles per gallon. Instead, stay cool by taking advantage of your car's air conditioner, which is designed to work with your car and keep you comfortable and your car as fuel-efficient as possible.