Answer:

Explanation:
The index of refraction is equal to the speed of light c in vacuum divided by its speed v in a substance, or
. For our case we want to use
, which for our values is equal to:

Which we will express with 3 significant figures (since a product or quotient must contain the same number of significant figures as the measurement with the <em>least</em> number of significant figures):

If argon could exist as a solid, 3200 m/s would best represent the speed through solid argon.
Answer:
a. 45 N. / b. 0.08 m/s^2. / c. 102 N
F = ma
F = 15(3)
F = 45 newtons
F/m = a
20/250 = a
0.08 m/s^2 = a
R = ma
R =1.5(68)
102 N
The local charging of the comb is due to induction. The negative object's charge pushes electrons in the comb away from the side close to the charged object causing that part to be positively charged. Note that the comb's net charge is still zero provided it doesn't touch the object. When you move the comb away its electrons will redistribute.
Where they slide over each other.
Transform boundaries are formed or occur when two plates slide past each other in a sideways motion. They do not tear or crunch into each other (but the rock in between them may be ground up) and therefore none of the spectacular features are seen such as occur in divergent and convergent boundaries.
In a transform boundary, neither plate is added to at the boundary nor destroyed. They are marked in some places by features like stream beds that have been split in half and the two halves moved in opposite directions.