Final answer:
Fog streams are less affected by wind compared to solid or straight streams, due to their wide angle spray pattern. Although they have a shorter reach due to dispersing water over a broad area, the increased water surface area exposed to the fire allows for rapid vaporization and effective heat absorption. The correct options are a and c.
Step-by-step explanation:
The characteristic of fog streams that distinguishes them from solid streams and straight streams is that they are less affected by wind than their counterparts. Fog streams produce a wide angle spray of small water droplets, which allows them to cover a larger area and protect firefighters by creating a barrier from the heat.
The presence of many small droplets increases the total surface area of water exposed to the fire, encouraging rapid vaporization and heat absorption. This effect, however, also makes the fog stream more susceptible to disruption by strong winds, as opposed to the more focused solid stream, which has more mass and cohesiveness to counteract wind.
When considering reach, fog streams do have a shorter reach than solid streams, but this is not the defining characteristic that was being sought in the question. The reach of the fog stream is less due to the spray pattern dispersing water over a broad area.
Solid streams are concentrated and thus can be directed further. Additionally, because fog streams expose more surface area of water to the environment, they also have a greater potential to absorb heat from the fire, which is beneficial in firefighting operations.
Hence, Options a and c are correct.