.
As you move from left to right, the atomic number of each element increases
by

Ionization Energy increases from left to right on the periodic table. Atomic radius decreases moving left to right on the periodic table.

Atomic size gradually decreases from left to right across a period of elements. This is because, within a period or family of elements, all electrons are added to the same shell.

b. examine and describe cells

the answer is 303.15 or 303