On increasing the temperature of a substance gradually, which of the following colours will be noticed by you?

The variation of radiant energy emitted by the Sun, the filament of a tungsten lamp, and a welding arc as a function of its wavelength is shown in the figure. Which of the following options is the correct match?

Which one of the following is the $\nu_{m}-T$ graph for a perfectly black body? Here, $\nu_{m}$ is the frequency of radiation with maximum intensity and $T$ is the absolute temperature.

The surface temperature of the sun which has maximum energy emission at $500 \,nm$ is $6000 \,K$. The temperature of a star which has maximum energy emission at $400 \,nm$ will be: (in $\,K$)

The wavelength of maximum intensity of radiation emitted by a star is $289.8 \, nm$. The radiation intensity for the star is: (Stefan's constant $\sigma = 5.67 \times 10^{-8} \, W m^{-2} K^{-4}$,Wien's constant $b = 2898 \, \mu m \cdot K$)

The minimum temperature of a body at which it emits visible light is approximately.......$^oC$.