Which power regarding the federal judiciary was
established in marbury v. madison?
(1) the president appoints all federal judges.
(2) the congress creates lower federal courts.
(3) members of the federal courts serve life
terms.
(4) federal laws may be declared unconstitutional.

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.