Select the choice that best describes the relationship of the pair of compounds. Both compounds are alkenes. Carbon 1 of both alkenes contain an ethyl and a hydrogen. Carbon 2 of both alkenes contain a methyl and a hydrogen. Compound 1 has the ethyl and methyl group on the same side of the alkene. Compound 2 has the ethyl and methyl group on opposite sides of the alkene. The compounds are: geometric or cis/trans isomers the same compound constitutional isomers not isomeric

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.  

i think its 100

i hope this !