In 1887, Ralph Abercromby and Hugo Hildebrandsson expanded Howard's original cloud classification system and published a classification system that, with only slight modification, is still in use today. In their system, ____ principal cloud forms are divided into ____ primary cloud groups.
A)eight; two
B)nine; three
C)ten; four
D)eleven; five
E)twelve; six

Question

Quizplus · Accepted Answer

Ten principal cloud forms are divided into four primary cloud groups in the system developed by Ralph Abercromby and Hugo Hildebrandsson, which expanded on Howard's original cloud classification.

In 1887, Ralph Abercromby and Hugo Hildebrandsson Expanded Howard's Original