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 the Wall Street Journal nearly two-thirds of the flights of Comcast's $40 million corporate jet purchased for business travel related to the NBCU acquisition, were to CEO Brian Roberts' private homes or to resorts.". Is that enough to answer the question?