You're starting a new equity long/short hedge fund with $100 million. Why do you need to hire a prime broker from a bulge bracket bank, and how exactly do they make money off you?

你刚成立了一家一亿美元规模的多空对冲基金。为什么你需要雇佣华尔街大行的主经纪商（Prime Broker）？他们具体是怎么从你身上赚钱的？