It might be zero for some people, but it's actually-- it is--the standard rate for people who have not negligible income is 15%.

对某些收益较少的人来说税率是零,但实际上...,对于大部分投资获利的人来说,标准税率是15%

耶鲁公开课 - 金融市场课程节选

So with problems at zero, ; which will be posted in two forms; PDF PDF for standard and PDF for hacker on cs50.net tonight, you will have the choice of implementing pretty much any scratch projects you can think of, and which subject to very few constraints.

对于问题集，我们提供了;,标准PDF以及可编程,今晚它们都会被放在CS50，net上，你可以选择任何,你想到的项目，范围不限。

哈佛公开课 - 计算机科学课程节选