Phoebe is taking samples from a lake to determine how the populations of aquatic life change during the summer. Each week for a month she takes samples from different areas of the lake. Over the course of a month, she finds the marine life listed in the chart below. What should Phoebe change about her methodology to better address her question?

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Question

Phoebe is taking samples from a lake to determine how the populations of aquatic life change during the summer. Each week for a month she takes samples from different areas of the lake. Over the course of a month, she finds the marine life listed in the chart below. What should Phoebe change about her methodology to better address her question?

IMAGE LINK:
https://www.connexus.com/content/media/369615-8242011-124611-PM-2073751595.png

anonymous · Answer

A. Collect samples more frequently than once a week.
B. Provide details about the creatures in the "other" category.
C. Take samples from the same location each time.
D. Use a more sophisticated net to collect smaller creatures.

blues · Answer

Which do you think it is?

anonymous · Answer

I think its B?? but im not sure...

blues · Answer

I think it's C again.

The point of the study is to look at change over time. The study collection method - picking different sites - introduces the possibility that the change seen is due not to change over time but to intrinsic differences between the sample sites. Picking samples from the same site would eliminate that second possible cause of difference.