World Populations SQL Practice

Question 8. What is the difference in population between 2000 and 2010 in Indonesia?

The above question is stumping me especially since the SQL course hasn’t taught how to do basic arithmetic yet. I don’t want to be given the answer but I’d like some examples that show how to do addition, subtraction, etc. so I can arrive to the answer on my own.

https://www.codecademy.com/practice/projects/world-populations-sql-practice

Try to make two columns with year and population. It’s enough)