Of course it’s 40. Anyone who doesn’t understand what a square is needs to go back to elementary school.
And the reason these posts with the “heated argument” crap exist is the same reason morons post junk like “I bet you can’t think of a city that doesn’t have the letter E!” It’s so they can get suckers to post comments and share it to their friends, thus increasing their exposure and hopefully getting more likes. And people just eat it up, not realizing what saps they are.