What compound is composed of deoxyribose sugars and nitrogenous bases

Deoxyribonucleic acid (DNA) is a long, double-stranded, helical molecule composed of building blocks called deoxyribonucleotides. A deoxyribonucleotide is composed of 3 parts: a molecule of the 5-carbon sugar deoxyribose, a nitrogenous base, and a phosphate group.

explanation:

let the different atoms be x and y. each with four protons and same mass will be represented as follows.

mass number is number of protons + number of neutrons.

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since, it is given that one has a negative charge while the other is neutral. therefore, there will be increase in number of protons and the atom will be represented as follows.

according to periodic table, mass number of beryllium is 9 and it has atomic number 4 so, the atoms will be and .  

the protons and neutrons will be located inside the nucleus whereas the electrons will be revolving around the nucleus.