Answer
Applying Wein's displacement
1) for sun T = 5800 K
2) for tungsten T = 2500 K
3) for heated metal T = 1500 K
4) for human skin T = 305 K
5) for cryogenically cooled metal T = 60 K
range of different spectrum
UV ----0.01-0.4
visible----0.4-0.7
infrared------0.7-100
for sun T = 5800
λ 0.01 0.4 0.7 100
λT 58 2320 4060 5.8 x 10⁵
F 0 0.125 0.491 1
fractions
for UV = 0.125
for visible = 0.441-0.125 = 0.366
for infrared = 1 -0.491 = 0.509