Two vessels of different materials are identical in size and wall-thickness. They are filled with equal quantities of ice at `0^(@)C`. If the ice melts completely in 10 and 25 minutes respectively, compare the coefficients of thermal conductivity of the materials of the vessels.

Explanation

To solve the problem, we need to compare the coefficients of thermal conductivity of the materials of the two vessels based on the time it takes for the ice to melt in each vessel.

### Step-by-Step Solution:

1. **Understanding the Problem**:
- We have two vessels made of different materials but identical in size and wall thickness.
- Both vessels contain equal quantities of ice at 0°C.
- The ice in the first vessel melts in 10 minutes (let's call this time \( T_1 \)).
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