Final answer:
Alice's favorite spots along the path to the river can be marked at various distances from her starting point.
Step-by-step explanation:
Alice's favorite spots along the path to the river can be determined by looking at the distances she walked. If the river is 1 mile away from Grandpa's house, Alice's favorite spots could be marked at various distances from her starting point. For example, one favorite spot could be 0.25 miles away from Grandpa's house, another spot could be 0.5 miles away, and another spot could be 0.75 miles away.