Match the following concentration methods with the principle behind them.

1. Levigation is used to concentrate ores by passing stream of water over them and washing away the lighter impurities.
Principle used- difference in specific gravities of the ore and impurities

2. Magnetic separation is used to concentrate an ore if either the ore or the impurity is magnetic in nature.
Principle used- difference in magnetic property between the ore and impurities

3. Froth flotation is used to concentrate sulphide ores. Ores are preferentially wetted by oil whereas gangue particles are preferentially wetted by water.
Principle used- differential wetting property of ore and impurities