Separation of $\text{DNA}$ fragments is done by a technique known as :

In Southern blotting,which of the following is separated by gel electrophoresis?

How many steps are there in one $PCR$ cycle?

Consider the following statements about $PCR$:
$I.$ Polymerase Chain Reaction $(PCR)$ is a technique of synthesizing multiple copies of the desired gene in vitro.
$II.$ This technique was developed by Kary Mullis in $1985$.
$III.$ $A$ single $PCR$ amplification cycle involves three basic steps: denaturation,annealing,and extension.
Which of the statements given above are correct?

$PCR$ (Polymerase Chain Reaction) is used for the diagnosis of which of the following diseases?

$DNA$ precipitation out of a mixture of biomolecules can be achieved by treatment with