Answer:
D. because the light is reflected back into the fiber along its sides
Explanation:
The fiber is constructed in a way that the light is bent/reflected/refracted toward the center core of glass. So, from the center core, there is a layer above it that has a different propagation than the core, and above that the same thing. To give you a real world visual example, if you look down in a pool of water, then stick a straight stick into it, you see that the straight stick appears to bend. That is what is happening to the light as it travels through a different medium (air to water). This same effect is incorporated in the fiber optic cable construction.
It is B since they are traveling at the same speed one is positive so the other had to be negative hope this helps;)))))
Comparative investigation is a research method that makes comparison across different countries of the world. Limitation : data set in different countries may be defined differently. Benefit : the method is flexible.
They are blue because of hydrogen helium and methane
