Hello There!
Kilo means thousand.
For example:
Kilometer means a thousand meters.
Hope This Helps You!
Good Luck :)
If speed = distance/time , then time = speed/distance.
So...
Speed of light = 3*10^8(m/s)
Average distance from Earth to Sun = 149.6*10^9(m)
Therefore, t=(3*10^8(m/s))/(149.6*10^9(m))
I hope this was a helpful explanation, please reply if you have further questions about the problem.
Good luck!
The heat (energy) needed to raise the temperature of the water is given by

The wavelength of the radiation of the oven is

, so the energy of a single photon of this radiation is

So, the number of photons required to heat the water is the total energy absorbed by the water divided by the energy of a single photon:

photons
Their combined momentum after they meet is 0 .