Safety precautions taken while determining the melting point of naphthalene using cooling curve

What precaution should you take with naphthalene? Briefly explain why there is a constant-temperature plateau in the cooling curve in Figure 1 but not in Figure 2. Briefly explain why, in Figures 1 and 2, the temperature rises immediately after the first crystals appear. If you could only record a single temperature reading in a freezing point determination experiment, which temperature should you record? (This is the point that you should observe most carefully when carrying out the experiment.) Briefly explain why it is important for the beaker of water to cool slowly and for you to stir the naphthalene liquid as it cools.

Explanation:

change tension

i think the answer is a, hope this : )