Identify the major product ( $99 \%$ ) formed when $\left(\mathrm{CH}_3\right)_3 \mathrm{CH}$ is treated with $\mathrm{Br}_2$ in UV light.

Which among the following pair of properties are intensive?

Which of the following equations gives angular momentum of an electron in a stationary orbit?

Which element from following has lowest ionization enthalpy $\left(\mathrm{IE}_1\right)$ ?