Has mistakes in it. I've never met a textbook at any level. Even some of the classic text books that have been around forever have mistakes in them kinds of mistakes all different kinds of mistakes. And they're all gonna be in there somewhere other. There's gonna be mistakes and formatting the terminology or the symbolic g. or whatever that houston there. There's going to be typos. There's going to be things that get a little mixed up here and there. The on this happens a lot with labels on illustrations. You can keep bad this experience where you put the label backwards supposed to be and then at the next round and there are many rounds of checking things next round of proof eating reading. It's bounce back to the wrong spot and you put it back in next time. Run and bounce back again. And i don't i don't know how it happens. Probably a bunch of different ways. It can happen because lots of people working on these projects in. Sometimes it gets all the way through even though you've corrected at three or four times or maybe more and it still gets through. And i've also had situations where somebody has pointed out a typo and i go back and lincoln think was that in the prior edition. Did i introduce that typo or or what. Go back and look in. The type was been in there for three editions. How could that happen. You know a professional copy editors in professional proofreaders multiple authors and contributors reviewers looking at that in students countless students. Why didn't they say anything you know. Sometimes they do sometimes catch him and let us know and by the way when you catch a typo or some other kind of air please please please get in touch with the publisher and ask them to pass that along and they will we get those every once in a while in. It's either an opportunity to fix something in the textbook. That's going to help everyone or it's an opportunity to learn. We were the woods that are wrong. That happens sometimes. And i usually reach out if i know who it is. I reach out to them and say look. Here's why we did it this way and we think car reflects current understanding. And here's why. And we all have those things i mean. None of us can know everything about amp. So we all have our own misconceptions and in gaps in knowledge and things like that and speaking of that. That gets to this other kind of mistake. It's not just typos. There are content errors and their misconceptions in there. Because it's made by humans and we all have that and again reach out to the publisher who will get the information to the author. If you happen to know the author like you know me you don't have to get a hold of me directly. Tell me about it. I mean told me exactly. Don't say that one part where you talk about the heart. That's going to help me much. But tell me this page or tell me the book too. Because i have more than one tax. So you contact. That author talked to that author. Don't do it while you're in a group of fifteen people..