Answer:
elements in the same column have the same number of neutrons. elements with similar mass are placed in the same column.
Answer:Why are temperatures higher in summer than in winter?
During the summer, the sun's rays hit the Earth at a steep angle. ... Also, the long daylight hours allow the Earth plenty of time to reach warm temperatures. During the winter, the sun's rays hit the Earth at a shallow angle. These rays are more spread out, which minimizes the amount of energy that hits any given spot.
Answer:


Explanation:
Here mass density of rod is varying so we have to use the concept of integration to find mass and location of center of mass.
At any distance x from point A mass density


Lets take element mass at distance x
dm =λ dx
mass moment of inertia

So total moment of inertia

By putting the values

By integrating above we can find that

Now to find location of center mass


Now by integrating the above


So mass moment of inertia
and location of center of mass 
<span>Energy exists as light, heat, sound, mass, moving objects, gravity, fuel, chemicals, and electricity.</span>
We are in the lowest layer called Troposphere.
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