Manu was heating oil to fry potato chips. The cooking oil all of a sudden caught fire, he poured water to extinguish the fire. Do you think, this action was suitable? If yes, why? If not, why not? In such a condition what should Manu have done?

Pouring water to extinguish the fire due to oil was not suitable action.
It is because oil is lighter than water hence, water will settle down below the oil. The oil floats on water and continues to burn.
In such conditions, sand or soil should be used. They cut off the supply of air to the fire. Thus, fire can be controlled.
[But sand or soil will not be available at that place.]
Steps that should have been taken by Manu
Manu should have switched off the flame of the burner and put a lid on the frying pan. By doing this, the contact between fuel and oxygen is cut off and the flame will go off.

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