Answer:1. Filtering is the process of removing unwanted substances from a liquid or gas by passing it through a filter medium, which allows the desired fluid to pass while retaining solid particles or impurities.2. Sieving is the process of separating materials based on size by passing them through a sieve or mesh, allowing smaller particles to pass through while retaining larger ones.3. When filtering, filter cloth or filter paper is used as the material to separate mixtures, effectively trapping solid particles while allowing the liquid to flow through.