I need to mention at this point what the law of the lover is, because you'll hear that used a lot of times. If you think of that the old Seasaw or Teaphtotter or whatever it was you grew up calling it probably before safety people said it was unsafe for you to actually ride one of these things in the playground, you always know that you have to put the lighter people farther away from the full-crown. So, my mom and dad would ride the Cedar Totter closer to the middle than you would. In general, when we're talking about the law of the lover what we mean is that F A is equal to G B. So, whatever two forces you have, if they're acting along a single line, you know actually have to take some of the moments at the full-crown with the whole co-science and science thing. The law of the lover says that you can just say along the lever as well. Now, how does that work? We know that moment has to be summed in a perpendicular distance. But the reality here is that my lever is a single line. So, whenever angle is acting at the bottom of the lever is acting at the top of the lover too. So, if I broke my forces up, both of them perpendicular to and along the actual lever, I could sum the moments here at this full-crown and see what happens. So, this would be F cosine theta and G cosine theta were perpendicular to the actual lever. F sine theta and G sine theta are a long lever. Now, forces along the direction of the lever aren't going to cause a moment at O. So, what I end up here with is F cosine theta times A and G cosine theta times B. Well, of course the cosine theta is going to cancel. This is generally not a huge topic. It's just something that if you notice it, can shortcut your work.