Help me in solving GSQ66 problem

help
,
1

My issue

Run time error

My code

/* Write a query using union to stack the table 'Arts' over 'Science' and output the final table */
SELECT student_id, student_name, department
FROM Arts
UNION
SELECT student_id, student_name, department
FROM Science;

Learning course: Database management systems
Problem Link: Union in Database management systems