as you'll find out in your homework assignment.

解决这个问题
So how are we going to model this on the homework?

那么我们作业中要如何建立模型呢
The way we're going to model differentiated products

我们建立差异产品模型的方法
is to imagine, just to take a simple example,

想象一下举个简单的例子
imagine a city and this city has one long straight road through it.

想象一个被一条直路贯穿的城市
So this city is not a city in New England,

所以这不是在新英格兰的城市
it's a city in the Midwest,

它是美国中西部的城市
where everything's flat and the roads just go completely straight.

那里都是平坦而笔直的路
You can think of this as being a mile long.

你可以假象它有一英里长
It doesn't really matter,

这其实无所谓
let's just think of it as being a mile long.

就想象成一英里长吧
We're going to assume that

我们假设