Fred, a manager at ABC Company, had been trying to figure out a better way to make the shipping faster and easier. After recognizing the problem, he immersed himself in research and looked to see how other companies handle shipping in order to understand all the options, and he worked on the problem for months trying to figure out a solution. For a couple of weeks, Fred set the problem aside and did not think about it for a while. During this time, Fred's brain was actually working on the problem unconsciously. What is this called