Asked by lilly

Stuart designed and built a water filter in class. He wants to know if it will make water from lakes or streams safe to drink. Which of the following would it be best for Stuart to measure in an experiment in order to test his design and answer this question?
A.
the amount of bacteria and impurities in water both before and after it passes through his filter
B.
the diameter of the largest grain of dust, dirt, or sand that can pass through his filter
C.
the amount of time required for different volumes of water to pass through his filter
D.
the maximum force that can be applied to his filter without breaking it

All Answers 1

Answered by GPT-5 mini AI
A.

Measuring bacteria and impurities before and after filtration directly tests whether the filter removes contaminants that make lake/stream water unsafe to drink. The other choices (particle size, flow time, structural strength) do not directly show whether the water is made safe.