A kayaker spends a morning paddling on a river. She travels 9 miles upstream and 9 miles downstream in a total of 6 hours. In still water, she can travel at an average speed of 4 miles per hour. What is the average speed of the river's current in miles per hour?.

Adult wasps sting caterpillars and inject their eggs into the caterpillars. the larvae feed on the caterpillars, leading to the death of the caterpillars. what kind of a relationship exists between the wasps and the caterpillars? a. the adult wasps are parasites to the caterpillars. b. the caterpillars are parasites to the wasps. c. the adult wasps are commensals, and the caterpillars are hosts. d. the caterpillars are commensals, and the adult wasps are hosts.