3. Apart from dabbling in playwriting, he has tried creating a great epic novel and composing a long, tragic epic.
Explanation:
Parallel structure creates a flow to a sentence because all clauses or phrases are structured in the same format. This can include using the same verb tense and verb ending. In number 3 all the verbs are in present tense and end in ing (dabbling, creating, composing). This creates correct parallel structure in the sentence.
The answer is in the pictures, "The weather was a powerful force in the lives of the Norse". Being at the mercy of something means that you are being over-powered by the force.