Very simply, I think that they may block the sun's rays from reaching the Earth, cooling down the planet, or they may eventually end up being turned into acid rain and rain back down to the Earth.
A force can make an object stop or slow down. Friction is the contact force that slows down or stops an object. Friction is results when two materials rub against each other. When that object is in motion, the friction forces that object to slow down/stop.
Your answer is false some birds use echolocation to
