Answer
The heating curve of that process is represented by the drawing:
- The segment represented by "3" corresponds to the liquid physical state, that occurs between 0 and 100$^{\circ}$ C.
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Work Step by Step
You can use the Figure 3.8 (Page 81) as the basis to draw the heating curve.
Since the melting/freezing point of water is at $0^{\circ} C$, and the boiling point is at $100^{\circ}C$, at any value between these temperatures, water will occur as a liquid.