Answer:0.00000009
Explanation:
9.11 × (1/1000000000)=0.00000009
Answer:
126 m
Explanation:
Distance=time*speed➡42*3=126m.
The 2nd one I think but I need some points
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 :)
Answer:
Temporary in nature.
No new substance is formed.
Explanation:
Temporary in nature: Does not affect the internal structure of a substance, only the molecules are rearranged.
No new substance is formed: Most of the physical changes are reversible. We can obtain the substance back even after the change.
hope this helps
have an awesome day -TJ