The missing question is: how many photons are produced per second?
Answer:

Explanation:
The energy of a photon is given by

where
h is the Planck constant
c is the speed of light
is the wavelength of the photon
In this problem, the photons have wavelength
, so each photon has an energy of

The total energy emitted by the bulb in 1 second is
E = 100 J
Therefore, the number of photons emitted per second is

Answer:
The maximum current which can flow through a fuse without melting it, is called its rating. ... If current higher than 8 A flows through the fuse, it would melt and circuit gets broken. ... Hence, fuse acts as a safety device
Answer:
6
Explanation:
The rate of change in this scenario corresponds to the number of inches that Ree grows every year. Basically, Ree's height can be written as a linear equation as follows:

where
x is the number of years after the first birthday
y is the height in inches
q = 27 is the height of Ree on her first birthday
m = 6 is the inches gained by Ree at each birthday
So the equation can also be rewritten as
y = 6x + 27
Index of refraction can be calculated using the following formula:

where
in a vacuum and "n" is the index of refraction. So we must calculate our velocity by manipulating the index of refraction formula and isolate v and so:

We could go one by one and calculate the velocity or use logic. If you divide by a larger number the output will be a smaller number. Therefore, the answer would be n=1.62 is the slowest.

By that logic when n=1 light would travel the fastest of these four scenarios. The key thing to understand about these problems is that the speed of light slows down as it goes through a medium, in a vacuum it's 3 x 10^ 8 m/s but as it goes through say air or water light slows down.