Martin Cooper invented the cell phone
The 4 significant figures of 31,546,000 are all 8 of the digits.
Pb, if compared to Ca it is less reactive and it is a transition metal, and is highly stable alone.
Answer: The smell of hot sizzling food reaches you several metres away, but to get the smell from cold food you have to go close because the kinetic energy of the particles of matter increases with the increase in temperature. In cold foods, kinetic energy is less while in hot foods, kinetic energy is more
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