Why did merchants and traders build a series of oases along the Silk Road? to provide food, shelter, and protection for travelers to provide employment for peasants who lived nearby to establish retreats where new religions could flourish to create markets where goods could be traded and sold

What is the "great pacific garbage patch"? (a) a large area of marine debris concentrated by rotating ocean currents (b) a large area around the pacific rim where debris collects from natural disasters such as tsunamis (c) an area in the pacific ocean where trash is intentionally dumped due to lack of landfill availability (d) a large trash dump located in hawaii

Distance that lewis and clark traveled from st. louis to ft. clatsop near the pacific ocean.

How does central place theory explain patterns in the size and distribution of cities?