Yeah! I'd always wondered what that check-mark button on the calculator was for. :-) On a related note, ever since I was a kid, every calculator I've ever enco

Yeah! I'd always wondered what that check-mark button on the calculator was for. :-) On a related note, ever since I was a kid, every calculator I've ever encountered, I run the square root of 89, and if it returns 9.4339811(..32 on more powerful ones) and thereabouts, then I trust the calculator. Kids do weird stuff. Big kids continue it sometimes.