Which kingdom includes unicellular or multicellular eukaryotic organisms?

The figure shows the variation of photocurrent with anode potential for a photo-sensitive surface for three different radiations. Let $I_a, I_b$ and $I_c$ be the intensities and $f_a, f_b$ and $f_c$ be the frequencies for the curves $a, b$ and $c$ respectively.

In a Young's double slit experimental arrangement shown here, if a mica sheet of thickness $t$ and refractive index $\mu$ is placed in front of the slit $S_1$, then the path difference $(S_1P - S_2P)$

The moment of inertia of a sphere (mass $M$ and radius $R$) about its diameter is $I$. Four such spheres are arranged as shown in the figure. The moment of inertia of the system about the axis $XX'$ will be (in $,I$)

Identify the reagent used in the following reaction.
Benzoic acid $\stackrel{\text{Reagent}}{\Delta}$ Benzoyl chloride + Phosphorous oxychloride + Hydrogen chloride

Which of the following is added to chloroform to slow down its aerial oxidation in the presence of light?