PLEASE HELP MY TEACHER IS GRADING ME

Ascientist and her team counted 200 individual deer in an area of 10 square kilometers. what is the population density?

An ecologist studied the same species of deer during the summer and the winter. she noticed that during the summer, when there was plenty of food, the deer were energetic and playful. however, during winter when food was scarce, the deer moved more slowly and did not run unless they needed to escape a predator. which scientific fact is best supported by her observations?

Why did adult crab numbers decline in he ecosystem, even though sea stars were still available?