I want to know the answer to the following question:
In issuing the grade, the Corporate Library found that a third of Comcast's board was how old?
All the background I'm provided with is that "According to Corporate Library, Comcast's board of directors ability to oversee and control management was severely compromised (at least in 2010) by the fact that several of the directors either worked for the company or had business ties to it (making them susceptible to management pressure), and a third of the directors were over 70 years of age.". Is that enough to answer the question?