An example of brainstorming could be writing down your ideas then coming back to them later and adding onto them.
The answer would be complex sentence, because it consists of an individual clause (The explorers brightened the dark cave) and a dependent clause (when they lit a torch from their cooking fire).
Wait but why does he have clay
Answer:
March on Washington
Explanation:
see https://www.history.com/topics/civil-rights-movement/i-have-a-dream-speech