The value of $\sqrt{12\sqrt{5} + 2\sqrt{55}}$ is

Which among the following is a benzylic halide?

Which of the following groups of algae do not have eukaryotic organization?

$A$ radioactive sample of $U^{238}$ decays to $Pb$ through a process for which the half-life is $4.5 \times 10^9 \text{ years}$. What is the ratio of the number of nuclei of $Pb$ to $U^{238}$ after a time of $1.5 \times 10^9 \text{ years}$? (Given $2^{1/3} = 1.26$)

Name the plant whose leaves are economically important and earn foreign exchange.

An organic compound $X$ on treatment with pyridinium chlorochromate in dichloromethane gives compound $Y$. Compound $Y$ reacts with $I_2$ and alkali to form triiodomethane. The compound $X$ is