To solve this problem it is necessary to apply the concepts related to the change of Energy in photons and the conservation of energy.
From the theory we could consider that the energy change is subject to

Where
Initial Energy
Energy loses
Replacing we have that


Therefore the Kinetic energy of the electron once it has broken free of the metal surface is 0.8eV
<span>element X has 62 neutrons
The atomic number of an atom is the number of protons that atom has. And the mass number of an atom is the sum of the number of protons and neutrons an atom has. So to determine the number of neutrons, simply subtract the atomic number from the mass number. So
89 - 27 = 62
So element X has 62 neutrons.</span>
<span>1.37 m/s
Assuming her initial velocity is totally horizontal and her vertical velocity is only affected by gravity, let's first calculate how much time she has until she reaches the ledge 8.00 m below her.
d = 1/2AT^2
8.00m = 1/2 * 9.8 m/s^2 * T^2
Solve for T
8.00 m = 4.9 m/s^2 * T^2
Divide both sides by 4.9 m/s^2
1.632653061 s^2 = T^2
Take square root of both sides
1.277753 s = T
So we now know that she has 1.277753 seconds in which to reach a horizontal distance of 1.75 m. So how fast does she need to be going?
1.75 m / 1.277753 s = 1.369592 m/s
Since we only have 3 significant figures in our data, round the result to 3 figures giving 1.37 m/s</span>
The hottest would be the O type and the coolest is M