What is the maximum speed of photoelectrons that are emitted during the action of ultraviolet radiation with a wavelength

What is the maximum speed of photoelectrons that are emitted during the action of ultraviolet radiation with a wavelength of 150 nm on the surface of zinc. The work of electrons from zinc is 4.2 eV.

Einstein’s equation for the photoelectric effect: h * ν = A + m * v ^ 2/2.
The radiation frequency is ν = s / λ.
150 nm = 1.5 * 10 ^ -7 m, work function of electrons from zinc A = 4.2 eV = 6.72 * 10 ^ -19 J, electron mass m = 9.1 * 10 ^ -31 kg, velocity light s = 3 * 10 ^ 8 m / s, Planck’s constant h = 6.63 * 10 ^ -34J * s.
We have: h * c / λ = A + m * v ^ 2/2
m * v ^ 2/2 = h * c / λ – A
v ^ 2 = (2 / m) * (h * c / λ – A)
v = square root of (2 / m) * (h * c / λ – A)
v = square root of (2 / 9.1 * 10 ^ -31 kg) * (6.63 * 10 ^ -34J * s * 3 * 10 ^ 8 m / s / 1.5 * 10 ^ -7 m – 6.72 * 10 ^ -19 J) = 1.2 * 10 ^ 6 m / s.