Chloramphenicol and erythromycin (broad spectrum antibiotics) are produced by

The current $i$ in the circuit will be:

Which of the following concentration factors is affected by a change in temperature?

For three vectors $u, v, w$,which of the following expressions is not equal to the other three?

$A$ certain electronic transition from an excited state to the ground state of the $H$ atom in one or more steps gives rise to three lines in the ultraviolet region of the spectrum. How many lines does this transition produce in the infrared region of the spectrum?

If the lines $\frac{x - 1}{2} = \frac{y + 1}{3} = \frac{z - 1}{4}$ and $\frac{x - 3}{1} = \frac{y - k}{2} = \frac{z}{1}$ intersect,then $k =$