 Okay. So let's do another one of these ones, I guess, and calculate the average atomic weight of boron. And this one, I guess, is interesting because it's telling you these are the two main isotopes of boron, the two isotopes of boron that exist, because you can see this plus this equals 100 percent. But this says it's boron 10, but it doesn't exactly weigh 10 amu. And this one's 11, it doesn't exactly weigh 11 amu. Before we were taking that as to equal exactly, you know, it was an exact number. But anyways, let's just do our calculation. So I guess if you want me to, I'll write it down again. So the average atomic weight, in this case of boron, we're going to want to take the decimal of the first. So by about 100 percent, 19 here, I'm giving myself 2 a little bit. 3 percent is really long. Number 10, 0, 1, 2, 9, 4. So it's a different unit than the one we were doing before. Form of the same unit. I guess it's 80.7 percent. I can squeeze this in. 11.00 atomic weight of boron. Remember the formula. Just get the fraction and then multiply it by that. Okay, so 8, 3 divided by 100 times 10.01294. And hopefully you get the same answer as me. And we'll take it to 4 sig figs because of the 2 abundances. It's going to be 10.81. So hopefully by this time, these things are not that much of a hassle for you. If they are, keep watching, watch these videos again and again. Okay?