Separation techniques

What separation technique should be applied for the separation of iron filling mixed with sand ?

Suggest separation technique(s) one would need to employ to separate the following mixtures. (a) Mercury and water (b) Potassium chloride and ammonium chloride (c) Common salt, water and sand (d) Kerosene oil, water and salt

Describe a separation technique used to separate the pigmentss of ink .

Which separation technique is based on difference in the volatility of the of the substances to be separated ?