Calculate work done in raising a stone of mass 5kg and specific gravity 3 lying at the bed of a lake through a height of 4 metre.

Explanation

To solve the problem of calculating the work done in raising a stone of mass 5 kg and specific gravity 3 through a height of 4 meters, we can follow these steps:

### Step 1: Understand Specific Gravity
Specific gravity (SG) is defined as the ratio of the density of a substance to the density of water. Given that the specific gravity of the stone is 3, we can express the relationship as:
\[ \text{Specific Gravity} = \frac{\text{Density of stone}}{\text{Density of water}} = 3 \]

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