What is the threshold frequency $($in Hz$)$ for the photoelectric effect of platinum $(=5\mathrm{.}32$ eV$)?$

$1\mathrm{.}29$e$15$ Hz

What is the stopping potential $($in eV$)$ if the wavelength of the incident light is $210$ nm$?$

$0\mathrm{.}572$ eV

Estimate the power radiated $($in W$)$ by a human body $($assume a temperature of $37\mathrm{.}0$C$).($Approximate this as a rectangular solid of dimensions $1\mathrm{.}60$ m by $0\mathrm{.}300$ m by $0\mathrm{.}200$ m$.)$