Where is $BamHI$ located in $pBR322$?

Which enzyme is used to join the ends of two strands of nucleic acid?

$A$ : $Pst I$ generates single-stranded overhanging stretches in $DNA$ after digestion that facilitate ligation.
$R$ : These short extensions can form hydrogen bonds with their complementary counterparts,which are then sealed by $DNA$ ligase to form phosphodiester bonds.

Give the types and functions of the Nuclease enzyme.

Hind $II$ always cuts $DNA$ molecules at a particular site called recognition sequence and it consists of : (in $bp$)