Answer
The energy of a single photon of this electromagnetic radiation is $1.948\times10^{-19}J$.
Work Step by Step
*Strategy: We would use the following formula of Planck's theory
$E = h\times\nu$
$E$ : the energy of a single quantum (or in this case, photon)
$h$ : Planck constant ($h\approx6.626\times10^{-34}J.s$)
$\nu$ : frequency of radiation
Step 1: Find the known variables
We know the electromagnetic radiation has frequency of $2.94\times10^{14}s^{-1}$; so $\nu=2.94\times10^{14}s^{-1}$
Step 2: Do the calculation according to the formula
The energy of a single photon of this electromagnetic radiation is:
$E=h\times\nu=(6.626\times10^{-34})\times(2.94\times10^{14})\approx1.948\times10^{-19}J$