The work function (f) of some metals is listed below. The number of metals which will show photoelectric effect when light of 300 nm wavelength falls on the metal is

 $\begin{array}{cccccccccc}\mathrm{Metal}& \mathrm{Li}& \mathrm{Na}& \mathrm{K}& \mathrm{Mg}& \mathrm{Cu}& \mathrm{Ag}& \mathrm{Fe}& \mathrm{Pt}& \mathrm{W}\\ \mathrm{\phi }\left(\mathrm{eV}\right)& 2.4& 2.3& 2.2& 3.7& 4.8& 4.3& 4.7& 6.3& 4.75\end{array}$