Calculate the number of photons, from green light of mercury ( = 4961 ), required to do one joule of work.

Calculate the number of photons, from green light of mercury ( = 4961

1.	Calculate the number of photons, from green light of mercury ( = 4961 ), required to do one joule of work.
A.	4524.2 10<sup>18</sup>/m<sup>3</sup>
B.	2.4961 10<sup>18</sup>/m<sup>3</sup>
C.	2.4961/m<sup>3</sup>
D.	2.4961/m
Answer» C. 2.4961/m<sup>3</sup>