64 a fisherman traveled in a boat from point n upstream. after having traveled 6 km, he stopped rowing and 2 hour 40 min after first leaving n, he was brought back to n by the current. knowing that the speed of the boat in still water is 9 km/hour, find the speed of the river’s current.

Classify the polygon by its number of sides. state whether the polygon appears to be regular or not regular. a. heptagon, regular b. heptagon, not regular c. octagon, regular d. octagon, not regular

Suppose that 3% of all athletes are using the endurance-enhancing hormone epo (you should be able to simply compute the percentage of all athletes that are not using epo). for our purposes, a “positive” test result is one that indicates presence of epo in an athlete’s bloodstream. the probability of a positive result, given the presence of epo is .99. the probability of a negative result, when epo is not present, is .90. what is the probability that a randomly selected athlete tests positive for epo? 0.0297

Three baby penguins and their father were sitting on an iceberg 0.50.50, point, 5 meters above the surface of the water. the father dove down 4.74.74, point, 7 meters from the iceberg into the water to catch dinner for his kids. what is the father penguin's position relative to the surface of the water?