Which metal is used in particle bombardment (biolistics) for gene transfer?

The part of the plasmid that codes for proteins involved in the replication of the $pBR322$ plasmid is:

The method for separating $DNA$ fragments is . . . . . . .

$A$ simple segment of a $DNA$ strand is shown, which provides the base sequence for its complementary strand. If the sequence reads the same in both $5' \rightarrow 3'$ directions on the two strands, what is specifically indicated here?

The enzyme restriction endonuclease:

Restriction in Restriction endonuclease enzyme refers to