Which of these is $NOT$ a method to make host cells 'competent' to take up $DNA$?

What happens if a foreign $DNA$ fragment is inserted into the coding sequence of the $\beta$-galactosidase enzyme in a plasmid containing the coding sequence for the $\beta$-galactosidase enzyme?

$DNA$ can be introduced into any cell by:

At which stage of $PCR$,does the template join with the primer?

What is the effect of high temperature $(94^{\circ}C)$ on $DNA$?

Which of the following steps are involved in the process of recombinant biotechnology? Arrange in correct order.
$I.$ Extraction of the desired gene product
$II.$ Amplification of the gene of interest
$III.$ Isolation of a desired $DNA$ fragment
$IV.$ Ligation of the $DNA$ fragment into a vector
$V.$ Insertion of recombinant $DNA$ into the host
Correct order is: