Final answer:
Tropical and equatorial air masses are hot as they develop over lower latitudes due to direct sunlight, longer periods of daylight, and warm ocean currents.
Step-by-step explanation:
Tropical and equatorial air masses are hot as they develop over lower latitudes. This is because these regions receive more direct sunlight and have longer periods of daylight, resulting in more heating of the air. Additionally, tropical and equatorial regions are characterized by warm ocean currents, which further contribute to the hot temperatures of the air masses.