sentences: iron is always magnetic & iron filings are made of small pieces of iron ->  iron fillings are always magnetic  iron fillings are always magnetic & black pepper is always nonmagnetic ->  the mixture of iron fillings and black pepper is a mixture of magnetic and nonmagnetic material  the mixture of iron fillings and black pepper is a mixture of magnetic and nonmagnetic material & magnet can be used for separating a magnetic material from a mixture of a magnetic and nonmagnetic material -> magnet can be used to separate a mixture of iron fillings and black pepper