Question

example 8: pollution and fish populations
in a lake, fish population was 500 before a chemical spill, dropped to 200 after the spill, and rose to 400 after cleanup.
two students made the following claims:

• claim a: pollution harms fish populations, but cleanup helps recovery.
• claim b: pollution has no effect on fish populations.

question: evaluate both claims by determining which one is best supported by the data. explain why the other claim is not supported.

Explanation:

The fish population was 500 before the chemical - spill, dropped to 200 after the spill, indicating harm from pollution. Then it rose to 400 after cleanup, showing recovery due to cleanup. Claim B is not supported as there is a clear change in fish population related to pollution and cleanup.

Answer:

Claim A is best supported by the data. Claim B is not supported because the fish population decreased from 500 to 200 after the chemical spill, which shows that pollution had an effect on the fish population.