What do comets and asteroids have in common? Choices:
They are made of ice
They orbit the sun
They are made of metal debris
They are the center of the solar system

They both orbit the sun

Explanation:

They are both celestial bodies orbiting our Sun.

explanation:

detials on each model with digrams

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.