30.6 • 150 is the same as 4,500 + 90, or 4,590 million kilometers, oddly enough, this isn't one of the options for an answer. Perhaps there was a typo?
The Alveolar macrophages, Cilia and the mucus layer
Your answer is A) - a greenhouse effect
that happens also at large scale, when the atmosphere is playing the role of the windows and the climate on earth became warmer.
Answer:
the answer would be migration