We then cut a pocket inside of the backpack so we could put the speaker in it. We then test the backpack by just putting the speaker inside of the backpack to hear if the sound was loud enough. We then...

Solar cell phone chargers use solar panels to charge cell phone batteries. They are an alternative to conventional electrical cell phone chargers and in some cases can be plugged into an electrical...

A quad copter, also called a quad rotor helicopter or quad rotor, is a multi rotor helicopter that is lifted and propelled by four rotors. Quad copters are classified as rotor craft, as opposed...