Answer:
autobiography,
since she's writing it about herself
B. Zaroff respects Rainsford and thinks that he will be a worthy opponent.
Zaroff knows Rainsford is intelligent and will be a worthy oppenent because he hasn't had one thus far in his game. He's heard of Rainsford and is aware of his celebrated status as a renowned big game hunter so he's confident in him.
<span>Find a one or two-word combination from your own vocabulary that will generalize the idea. Hope this helps ;-)
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Chocolate was learned about when Europeans explored Africa. I do not know how did found out. I hope this answers the "when" part of the question