"Utility" would be the best option for "the level of satisfaction a need or want provides" in the realm of economics, since a person "utilizes" something in order to get this satisfaction.
Because it was harder to travel over moountains.
North Africa has vast oil and natural gas deposits, the Sahara holds the most strategic nuclear ore, and resources such as coltan, gold, and copper, among many others, are abundant on the continent. The region is full of promise and untapped riches - from oil and minerals...
hope i helped!!!
:)
