Spent is the most negative connotation.
Explanation:
Fatigued is to feel exauhsted.
Weary is lack of sleep, tiredness.
Tired is just a minimal drousy feeling.
And spent is as if your energy was all used up, consumed.
I think the answer is "In 1867, the United States bought Alaska from Russia for $7 million". When you ask the question "when" the question is asking about time. In this excerpt, when is answered by "in 1987". while the sentence supported it is the event that happened during that time, which is " The US bought Alaska from Russia for $7 million.
Answer: His
Explanation: His, brother is a singular indefinite pronoun; therefore, the singular form his agrees with the antecedent