A plane crashed into a mountain. The pilot and his elderly passenger were badly hurt. They had no food or water. The pilot finally found a stream. But his hands were very burned. He could not scoop up the water. The passenger was too weak to reach the stream. Yet the passenger's age helped them get water. Can you guess how?

food chain i would say only because there is competition on getting food and survival

its main object was the establishment of "settlement houses" in poor urban areas, in which volunteer middle-class "settlement workers" would live, hoping to share knowledge and culture with, and alleviate the poverty of, their low-income neighbors.