1) Yes, some people tend to spell that wrong, will be changed when all pages receive their "review"
2) Googled it, you're right. No idea how that spelling mistake got into the bonus table
3) Googled it, correct spelling seems to be tradable. I've been using tradable on all my wiki pages but tradeable is used on the bonus table because that's how Jagex decided to spell it and for some reason we decided to stick with it
4) Thanks for noticing, will be changed accordingly
5) As I said before, these small spelling mistakes will be changed when all pages receive their "review"
Thanks for the feedback