Final answer:
Cloud droplets must increase in volume by roughly a million times to form precipitation, allowing them to become large enough to fall to the ground.
Step-by-step explanation:
For precipitation to form, cloud droplets must grow in volume by roughly a million times. This growth allows the droplets to become heavy enough to overcome air resistance and fall as precipitation, such as rain, snow, sleet, hail, or freezing rain. Clouds contain tiny droplets of water that need to aggregate around nuclei, which can be dust particles, ice crystals, or particles of silver iodide, to reach the critical size necessary for precipitation to occur.