<h2>
Answer:</h2>
The variables in the two-way table are:
period number and study group number
<h2>
Step-by-step explanation:</h2>
We know that the variables are the quantities which vary or changes with reference to some condition or some information.
A two way table is a table which is used to represent the relationship between two variables.
Here with the help of the table provided to us we observe that the table represents the relationship between two variables.
One is a study group number ( i.e. Group-1 and Group-2)
and the other is a period number (i.e. 3rd Period and 4th Period )