Study the given below single strand of deoxyribonucleic acid depicted in the form of a "stick" diagram with 5' - 3' end directionality, sugars as…

Study the given below single strand of deoxyribonucleic acid depicted in the form of a "stick" diagram with $\displaystyle 5$' - $\displaystyle 3$' end directionality, sugars as vertical lines and bases as single letter abbreviations and answer the questions that follow.

Name the covalent bonds depicted as (a) and (b) in the form of slanting lines in the diagram.

How many purines are present in the given "stick" diagram ?

Draw the chemical structure of the given polynucleotide chain of DNA.