Which molecule or reaction supplies the energy for polymerization of nucleotides in the process of transcription?

Answer to this is "the phosphate bonds that are present in the nucleotide triphosphate serves as the substrates" in the process of transcription.

Transcription is the process in which DNA is transformed into RNA with the help of an enzyme known as RNA-polymerase. RNA and DNA are the nucleic acids which are formed by linking the nucleotides together.

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.

            and  

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.