Imagine you're hiking through the woods, following some new trails. The weather is perfect, and you are relaxed. As you walk along, you notice the landscape beginning to change as you enter unexplored, rugged wilderness. Eventually, you stop to sit on a large rock and eat a snack.

As you are eating, you realize that you have no idea where you are. You forgot to bring a map and neglected to plan a route or mark your path. Now you feel a sudden burst of tension and fear. You are lost. You want to move faster—either continuing in the direction you were going or turning around to find your way back. But you know that panicking and running in any direction is a big mistake when you're lost in the woods.

You remember some crucial ...

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