Respuesta :
he should have multiple bottles of different types of lake water or stream water , run them through the water filter and then test each result with pH paper, as pH paper will tell if it's safe or not safe to drink
Answer:
The correct answer is "The amount of bacteria and impurities in water both before and after it passes through his filter"
Explanation:
Although each of these properties of Stuart's filter may be worth testing, the one that will tell him whether his filter can make lake water safe to drink is the amount of bacteria, parasites, and impurities in water both before and after it passes through his filter. Some filters are good at removing impurities, but not bacteria. Other ways of purifying water may kill bacteria but not remove impurities.