Part a
Answer: 
For the arrangement considered in part a, all the atoms are aligned side by side along the side of the square surface.
Along one side of the square, the number of atoms that could fit 
This is along one side. On the entire surface:
Number of atoms 
Part b
Answer: 
consider the attached figure below:
The next layer of atoms are filled in the depressions of the first layer. The vertical distance between the two atoms would change. Consider an equilateral triangle drawn by joining the centers of the three atoms.
The atoms along the horizontal side would be aligned side by side; same as above 
The number of atoms along vertical side would vary. vertical distance between two atoms can be calculate using equilateral triangle as shown below.
an equilateral triangle has all the angles 
Let the vertical distance be y.
Then, 
where r is the radius of each atom. 

The number of atoms along the vertical side 
Total number of atoms in this kind of arrangement 
Answer:
heat, energy that is transferred from one body to another as the result of a difference in temperature. If two bodies at different temperatures are brought together, energy is transferred—i.e., heat flows—from the hotter body to the colder. example: stove
Explanation:
hope this helps
Explanation:
Given that,
Distance 1, r = 100 m
Intensity, 
If distance 2, r' = 25 m
We need to find the intensity and the intensity level at 25 meters. Intensity and a distance r is given by :
.........(1)
Let I' is the intensity at r'. So,
............(2)
From equation (1) and (2) :



Intensity level is given by :
, 

dB = 32.96 dB
Hence, this is the required solution.
I was about to say: because people generally get comfortable with
what they think they know, and don't like the discomfort of being told
that they have to change something they're comfortable with.
But then I thought about it a little bit more, and I have a different answer.
"Society" might initially reject a new scientific theory, because 'society'
is totally unequipped to render judgement of any kind regarding any
development in Science.
First of all, 'Society' is a thing that's made of a bunch of people, so it's
inherently unequipped to deal with scientific news. Anything that 'Society'
decides has a lot of the mob psychology in it, and a public opinion poll or
a popularity contest are terrible ways to evaluate a scientific discovery.
Second, let's face it. The main ingredient that comprises 'Society' ... people ...
are generally uneducated, unknowledgeable, unqualified, and clueless in the
substance, the history, and the methods of scientific inquiry and reporting.
There may be very good reasons that some particular a new scientific theory
should be rejected, or at least seriously questioned. But believe me, 'Society'
doesn't have them.
That's pretty much why.
They are fused in the core of the star due to great pressures and temperatures. They are made all the way through iron. At that point the star dies. If it is a really large star it will become a supernova when it dies, creating all of the elements beyond iron as well, but only in its death. No star can create anything beyond iron in its life cycle