In a meter bridge,a $30 \Omega$ resistance is connected in the left gap and a pair of resistances $P$ and $Q$ in the right gap. Measured from the left,the balance point is $37.5 \text{ cm}$ when $P$ and $Q$ are in series,and $71.4 \text{ cm}$ when they are in parallel. The values of $P$ and $Q$ (in $\Omega$) are:

Which of the following statements is consistent with halophiles?

For any integer $n \geq 1$,the sum $\sum_{k=1}^n k(k+2)$ is equal to

Which of the following enzymes is used for joining $DNA$ fragments?

The correct statements $(s)$ about intermolecular forces is$(are)$
$(A)$ The potential energy between two point charges approaches zero more rapidly than the potential energy between a point dipole and a point charge as the distance between them approaches infinity.
$(B)$ The average potential energy of two rotating polar molecules that are separated by a distance $r$ has $1 / r^3$ dependence.
$(C)$ The dipole-induced dipole average interaction energy is independent of temperature.
$(D)$ Nonpolar molecules attract one another even though neither has a permanent dipole moment.