A biologist is using a dichotomous key to identify fish. 1. (a) Has a single dorsal fin ® 5 (b) Has a double dorsal fin ® 2 2. (a) One fin is spiny, the other is smooth ® 3 (b) One fin is not spiny or smooth ® 4 5. (a) Has small fin on back near tail ® 6 (b) Has no fin on back near tail ® 7 6. (a) Has barbs near the mouth ® Catfish (b) Does not have barbs near the mouth ® 10 7. (a) Tail is asymmetrical ® 8 (b) Tail is symmetrical ® 9 10. (a) Scales are small ® Trout (b) Scales are large ® Whitefish What is the next step to take to identify a fish that has a single dorsal fin and no fin on the back near the tail?