Do cold air masses and hot air masses automatically combine?

If the boundary between the cold and warm air masses doesn't move, it is called a stationary front. The boundary where a cold air mass meets a cool air mass under a warm air mass is called an occluded front. At a front, the weather is usually unsettled and stormy, and precipitation is common."

Explanation:

a. decomposes use carbon from dead organisms as fuel for cellular respiration, returning carbon dioxide back into the atmosphere.