If you change the subscripts it would change the reactants or products and then you would be solving a different formula, you would change what the chemical is
Answer:
option b is the correct answer
Maybe her old shoes had soft worn out bottoms and she slips in them. So her new shoes had more grip than her old ones so they kept her from falling.
Because the physical appearance change hope this helps
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Answer:
hot air rises because gases expand as they heat up.When air heats up and expands,its density also increases.The warmer,less dense air effectively floats on top of the colder, dense air below it. This creates a buoyant force that causes warmer air to rise.
cold air sinks because it is heavier as its more dense ( because of closely packed molecules) soits harder for them to move and they absorb less energy. Also, gravity pulls on it more strongly.
Hope it helps :)
