How has the Sahara desert been able to expand over time? (Explain the process of desertification)

Drought in the Sahel in the 1970s and 1980s made it look like the desert was expanding, because the reduction of rainfall at the desert margin (the Sahel) caused a reduction in vegetation. Warm, moist air rises near the equator, then cools and condenses its moisture, which falls as rain or snow

vertical merger is the term used for the joining of two or more firms involved in different stages of producing the same good or services.

explanation:

answer; have joints that fail from excess by early the accumulated effects of unnoticed infections,all of these things are possible for a person born without the ability to feel pain;