53. the columbia plateau in the northwestern u. s. was constructed (built up by) a, a shield volcano b. repeated violent eruptions c. a series of fissure eruptions that released a huge volume of low-viscosity basalt flows d. a series of subaqueous lava flows

c. a series of fissure eruptions that released a huge volume of low-viscosity basalt flows

Explanation:

The Columbia Plateau in the northwestern U.S, commonly known as the Columbia Basalt Plain as well, is a pronounced geographic area located in the interior Columbia River Basin. It originated at a point between six million and sixteen million years ago due to a series of flows of basalt.

81 is a composite number.

i only have few minutes according to the map above, which shows religious cultural regions, what two religions are most commonly practiced in africa? a. christianity and buddhism b. buddhism and hinduism c. islam and christianity d. hinduism and islam