If the weight of an object in air and in a dense liquid are $W_a$ and $W_l$ respectively, then upthrust :

To find the density of a liquid, a student used the following steps. The sequence of steps followed is given. Identify the step which has an error.

1: Found the weight ($W$) of the body in air.

2: Collect displaced volume of water to know the volume $V$ of immersed body.

3: Found the weight $W_l$ of the body in water when immersed completely.

4: Found $\frac{W}{V}$ to get the result.