The c. volcanologist worked to determine when the volcano would next erupt.
Answer:
the weather effects our emotions
Explanation:
if it is raining most people become sad and when it is sunny most people become happy and energized
From the passage you posted, the sentence expressing certainty is 'This dark assertion will be illuminated later on'. We use 'will' when we believe that a future state is certain to occur. For the second sentence with an auxiliary verb, it is '<span>But if you'll unwrap that package you may see why you had me going a while at first'. However, it states a possibility, not a certainty.</span>