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.
Answer:
Because the reason he wants Caesar dead is that he resents how popular and god-like he has become
Explanation:
The conspiracy to murder Caesar was done by different people who had to unite to see their goal accomplished. Cassius wanted Caesar dead because of a different and less honorable reason from the others because while the others wanted Caesar dead because they were worried Caesar could become a dictator and harsh to the Roman people, Cassius wanted Caesar dead because he was jealous of his popularity.