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Which best explains why a hot air balloon floats? (A) The heated air expands to fill the balloon. The air in the balloon is now lighter than the surrounding air, causing the balloon to rise (B) The heated air expands to fill the balloon. The air in the balloon is now heavier than the surrounding air, causing the balloon to rise (C) The heated air contracts to fill the balloon. The air in the balloon is now denser than the surrounding air, causing the balloon to rise. (D) The heated air contracts to fill the balloon. The air in the balloon is now lighter than the surrounding air, causing the balloon to rise.
What is A, the heated air expands to fill the balloon, the air in the balloon is now lighter than the surrounding air, causing the balloon to rise.