The number of possible enantiomeric pairs that can be produced on monochlorination of $2$-methylbutane is

Which of the following has the largest population in a food chain?

If ${x^p}{y^q} = {(x + y)^{p + q}},$ then $\frac{dy}{dx} = $

$A$ long straight wire carrying a current of $30 ~A$ is placed in an external uniform magnetic field of induction $4 \times 10^{-4} ~T$. The magnetic field is acting parallel to the direction of current. The magnitude of the resultant magnetic induction in tesla at a point $2.0 ~cm$ away from the wire is
$\left(\mu_0=4 \pi \times 10^{-7} ~H/m\right)$

Arbor vitae is composed of

What is a conjugated protein called if it contains a carbohydrate as a prosthetic group?