 Hi, this is Dr. Don. Some people have been struggling with the Goal Seek, so I want to give you a little more help. Here is the Goal Seek tab with the model copied over correctly, and I'll just double-check there if I want to change that to 10 and make sure yes that model is working there. And if I change my unit variable cost to 50, also it's working. So I'm going to go back just to convince myself that the model is working. Now we want to use Goal Seek, and we want to get the difference delta to equal a specific value. Now I'm not going to use the 100,000 that you need to use. I'll show you how to do the process though. We go to Data, What-if Analysis, Goal Seek, bring up the dialog box. We want to get the difference delta, and I'm going to get it to 50,000, and we're going to change the unit variable cost, and I'm going to click OK. And it takes a second for it to run. It's trying out values, and it eventually gets the solution to get 50,000, and it shows the unit variable cost would have to be $158, which is logical because these two equations, the only difference is the fixed cost. So if both the unit variable costs and the outsourcing unit costs are the same, then we would get our $50,000. One hint, you want to leave the Goal Seek showing the values. You need to click OK. If you click Cancel, it will go back to the original values. So you want to click OK, and then that will leave the Goal Seek values that you need for me to grade. And again, you need to get this to 100,000, so you'll get a different value, but I hope this helps a little bit.