He says American forces will be able to defeat the Taliban and al-Qaida in Afghanistan as they made significant gains against insurgents in Iraq if the president sends enough troops and other resources to do the job.

VOA: standard.2009.09.22

Two significant digits is good enough.

个有效数应该绰绰有余了。

麻省理工公开课 - 固态化学导论课程节选

Two significant digits is good enough.

个有效数应该绰绰有余了。

麻省理工公开课 - 固态化学导论课程节选