We could write this as six choose two, six choose two, and we could just apply the formula for combinations. And if this looks completely unfamiliar, I encourage you to look up combinations on Khan Academy, and we go into some detail on the reasoning behind this formula. It actually makes a lot of sense. This is going to be equal to six factorial over two factorial, over two factorial times six minus two factorial. So six minus two, six minus two factorial. I'll do the factorial in green again. Six minus two factorial, and what's this going to be equal to?