Complementary $DNA$ $(cDNA)$ is complementary to

Who discovered "Reverse transcription"?

Which method did Meselson and Stahl use to separate $DNA$?

$A$: Kornberg enzyme is associated with the removal of primers and thymine dimers.
$R$: $DNA$ polymerase $I$ performs exonuclease activity in $5^{\prime} \rightarrow 3^{\prime}$ and $3^{\prime} \rightarrow 5^{\prime}$ directions.

If $E. coli$ was allowed to grow for $60$ minutes,then what would be the respective proportions of light and hybrid density $DNA$ molecules?

Bacteria were grown in a medium containing a heavy isotope of nitrogen $(^{15}N)$ for many generations,and all their $DNA$ contained only heavy nitrogen. $A$ bacterium of this type was transferred to a normal medium and allowed to duplicate. After two divisions,the distribution of heavy $DNA$ is likely to be: