The American Food and Drug Administration says R.F.I.D.tags act like an electronic safety net to make it easier to catch counterfeits.

VOA: special.2010.03.01

For the course's website, help@cs net there'll be support forms and an email address, help@cs50.net, that you can turn to and frankly this is more a commentary on our lack of social lives during the term.

对于课程网站，我们有支持表格和邮箱地址，有什么问题可以求助去它,这更像是在评论我们的学习生活太缺乏社交活动。

哈佛公开课 - 计算机科学课程节选

I am going to say if that electron is to stay in its orbit, that is to say it doesn't flee the atom, it doesn't collapse under the nucleus then the sum of the forces on the electron must be zero No net force. And so that will be the sum of a dynamic force plus an electrostatic.

如果电子会保持在它的轨道上运行,既不脱离原子的话，它就不会由于原子核对它的吸引力而被瓦解掉,电子所受的合力一定为零,由于没有合力,所以电子所受力为动态力和静电力的总和。

麻省理工公开课 - 固态化学导论课程节选

We'll post an announcement to the course's homepage at CS50.net on the top with a link.

我们会在课程的主页CS50，net上,张贴一个通告。

哈佛公开课 - 计算机科学课程节选