Explanation: 1 Mark each
We can separate them in various ways.
1. The mixture is taken and put into a beaker of water.
After a few seconds of stirring, since sugar is soluble in water, the sugar will dissolve into the water. 
2. If the mixture is now left undisturbed for a few hours, the leftover pebbles from the mixture will form a sediment on the bottom of the beaker. 
The top layer of clean water is transferred into another beaker.
3. We can also use filtration to remove the stones from the beaker instead of waiting for it to form a sediment.
4. The new solution is now heated to a boil and left to evaporate. After the water has evaporated, the sugar will remain behind in the beaker.
Thus the sugar and the stones are removed. 
5. So while separating sugar from the stones, the various processes involved are sedimentation/filtration, decantation, and evaporation.