Now look closely at the patterns in the table. Compare the elements in each column and row. What can we say about elements in the same group and elements in the same period of the periodic table?
Select all the correct answers.

1)The number of electrons in the second energy level increases by one down each column.

2)Elements in the same row have the same number of occupied energy levels.

3)For each column, the last occupied energy level has the same number of electrons.

4)The number of electrons in the first energy level increases by one from Li to Ne.