Mercury MetalIron OreCopper MetalMilkOmelette
Pure substances - Mercury Metal and Copper Metal - there's nothing but the metal itself inside them, so they are pure substances. Homogeneous mixtures - Milk - the components of milk are dissolved evenly throughout the substance; one swig of milk doesn't differ from the last - so it's homogeneous. Heterogeneous mixtures - Iron Ore - the word ore implies that there are impurities, so that means it isn't mixed evenly or pure, so it's heterogeneous. I'm not quite sure about the omelet. I'd have to say that's homogeneous, since the egg yolk and egg white are mixed evenly in solution with one another. It could be a pure substance though since it's technically all egg!
