Passage Summary: Adding lime to lakes can fix acid rain damage, but it's a temporary fix because the lime eventually washes away. If a lake's water cycles out faster than once every six months, it's considered too expensive to treat.

Reasoning: N/A

Analysis: This is a 'Must be True EXCEPT' question, so four of the choices will be logical deductions from the text, and one will not. The premises establish a strict cost-benefit rule: if the water replacement rate is high (more than once per six months), the lake is not a candidate for liming. We can infer that any lake currently being limed must have a replacement rate of at least six months. Be careful not to pick an answer that makes claims about the *effectiveness* of lime in fast-moving water; the text only limits candidacy based on *cost*.