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## Exercise 1 of 6
Loading a simple mixture of proteins

Wait for the program to load. Most of the menus are not yet available.
Only the `Help` and `Start` menus have any selectable items. Click on the `Start` menu.
Then click on `Start from beginning...`.

You need to start off with a very simple mixture that we can experiment with. The list of available mixtures that you get may not look exactly like this, but somewhere in the list there should be `Easy3_Mixture`. Select it and then click on the `OK` button.

As its name suggests, this mixture contains three proteins. The computer will ask which of the three you want to purify. Click in the edit box, type `2`, (or use the direction buttons) and then click on the `OK` button.

The computer will give protein 2 an enzymic activity and tell you about its stability. For the time being, you can ignore it and just click on the `OK` button.

The work area will clear and the menu will change. At this point, you are ready to do some experiments with the protein mixture.