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: atmosphere
Explanation:
We cannot see the surface of Mars because of its thick atmosphere and of the iron dust that kicks up
maybe if you look it up it will come up
The tension force being supplied by the rope is 245 N.
<h3>What is tension force?</h3>
- Tension force is the force exerted on a rope or cord due to the weight of an object suspended from it.
The tension force on the given rope due to the weight of the lamp hanging from the rope is calculated by applying Newton's second law of motion as shown below;
T = mg
where;
- m is the mass = 25 kg
- g is acceleration due to gravity = 9.8 m/s²
T = 25 x 9.8
T = 245 N
Thus, the tension force being supplied by the rope is 245 N.
Learn more about tension force here: brainly.com/question/12797227
Answer:HERE IS YOUR ANSWER
THE POINTS ARE
IF WE PUT THE OBJECT BETWEEN THE FOCUS
AND THE POLE
THEN THE IMAGE FORMED WILL be MAGNIFIED
If that’s not what you are looking for, try this one:
For concave mirror the virtual image is formed when the object is kept in between the pole and the focus.
Given here the "size of the image" is twice to that of the object.
Hence, it is consider that the magnification is +2.
So, the magnification value is positive and the image formed will be "virtual and erect". Thus, the object should be kept in between the "pole and the focus" in concave mirror."
Explanation:
