system
Medical AI Inquiry: You were designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.
user
Feature of slow filter (w.r.t. fast filter) is/are:
assistant
The correct answer is  Ans. is 'd' i.e. Takes more time for purification o Slow sand filter occupies large area (more space). o Slow and filter requires less skilled operation. o Slow sand filter removes more bacteria and has better bacterial control (99.9-99.99%) o Slow sand filter requires longer duration for purification. o Size of sand is smaller (0.2-0.3 mm).