Answer:
Molecules in both the metal and the surrounding air will start moving at higher speeds.
Step-by-step explanation:
Temperature is a measure of the average kinetic energy of the molecules in a body. Thus, as the temperature of a body increases, its molecules tend to move faster.
At a high temperature of 150°C, the molecules in the metal hot plate move faster. Similarly, this heat is also transferred to the surrounding air molecules and they too start moving faster.
Therefore at 150°C, molecules in both the metal and the surrounding air will start moving at higher speeds.