Which one has the highest boiling point?

$(\sqrt{3}+i)^7+(\sqrt{3}-i)^7$ is equal to (in $sqrt{3}$)

The radii of curvature of the faces of a double convex lens are $10\, cm$ and $15\, cm$. Its focal length is $12\, cm$. What is the refractive index of the glass?

Which type of primary xylem is present in the given figure?

Match the following columns and select the correct option:

$(a)$ Placenta	$(i)$ Androgens
$(b)$ Zona pellucida	$(ii)$ Human Chorionic Gonadotropin $(hCG)$
$(c)$ Bulbourethral glands	$(iii)$ Layer of the ovum
$(d)$ Leydig cells	$(iv)$ Lubrication of the penis

$(a)\quad (b)\quad (c)\quad (d)$

$A$ gaseous mixture consists of $16 \ g$ of helium and $16 \ g$ of hydrogen. The ratio $\frac{C_p}{C_v}$ of the mixture is