On which template strand of $DNA$ does continuous replication occur?

Replication was allowed to take place in the presence of radioactive deoxynucleotide precursors in $E. coli$ that was a mutant for $DNA$ ligase. Newly synthesised radioactive $DNA$ was purified and strands were separated by denaturation. These were centrifuged using density gradient centrifugation. Which of the following would be a correct result?

Name a few enzymes involved in $DNA$ replication other than $DNA$ polymerase and ligase. Name the key functions for each of them.

At the end of $DNA$ replication,the $DNA$ molecule has:

Given below are two statements:
Statement $I:$
$DNA$ polymerases catalyse polymerisation only in one direction,that is $5^{\prime} \rightarrow 3^{\prime}$.
Statement $II:$
During replication of $DNA$,on one strand the replication is continuous while on the other strand it is discontinuous.
In the light of the above statements,choose the correct answer from the options given below:

The protein that helps in opening the $DNA$ double helix at the replication fork is .......... .