Answer:

Explanation:
P = Power = 50 kW
n = Number of photons per second
h = Planck's constant = 
= Frequency = 781 kHz
r = Distance at which the photon intensity is i = 1 photon/m²
Power is given by

Photon intensity is given by

The distance is 
Answer:
a
Explanation:
I think its a its speed increases.....
If its atomic number is 48, then it has 48 protons in the nucleus
of each atom. Any more mass than that is supplied by the neutrons
that are mixed in there with the protons.
If the mass is 167, and 48 of those are protons, then there are
(167 - 48) = 119 neutrons
in each nucleus.
Shadows are the absence of light, they are created when an object blocks light. In other words, shadows are the product of light particles, known as photons. These particles “bounce off” of the object without reaching the other side. Therefore light by itself will not form a shadow.