Which of the following create surface currents?
• wind and friction between air and water
• differences in salinity and water temperature
• differences in water salinity and wind
• differences in water temperature and friction between air and water

For a comparative or experimental investigation, scientists often make a testable about a scientific question, and then they test it in the investigation. a. control b. hypothesis c. procedure d. system

State officials are considering constructing a road through a forested wilderness area. this action will likely affect the forest ecosystem in various ways. part a: predict how the construction of a road could negatively affect plants and animals in that ecosystem. (3 points) part b: describe one way that the construction of a road could have a positive impact of the forest ecosystem. (1 point)

What is the ecological role of food chains and food webs