Who provided the $X-ray$ diffraction data for $DNA$?

The distance between two adjacent base pairs in a $DNA$ double helix is:

The similarity between $DNA$ and $RNA$ is that both are

If the length of $E. \; coli$ $DNA$ is $1.36 \; mm$, calculate the number of base pairs in $E. \; coli$.

In the structure of $DNA$,a purine base of one nucleotide is linked to a pyrimidine base of the opposite nucleotide by which type of bond?

In $RNA$,the adenine base can pair with .......