请教个问题，垄断竞争部分，垄断竞争区别于完全竞争的特征之一，价格高于边
际成本，曼昆课本上有这么一段话：
In this relationship between price and marginal cost, we see a key
behavioral difference between perfect competitors and monopolistic
competitors. Imagine that you were to ask a firm the following question:
“Would you like to see another customer come through your door ready to
buy from you at your current price?” A perfectly competitive firm would
answer that it didn't care. Because price exactly equals marginal cost,
the profit from an extra unit sold is zero. By ontrast, a
monopolistically competitive firm is always eager to get another
cusomer. Because its price exceeds marginal cost, an extra unit sold at
the posted price means more profit.

价格高于边际成本，多卖就可以增加利润？不对吧，企业已经在利润最大化的位置
生产了，价格高于边际成本，并不意味着边际收益也大于边际成本呀？ 不明白，
请指点。