I'd say the cable is about 1 metre long or maybe a bit less. As for the extension cable, I'm not sure but I think it doesn't exist in the original Asus, but there must be some on amazon or on the Chinese market.

According to my research, I cannot confirm this with a guarantee, as the manufacturer does not provide any information about which card was installed. According to the "teardowns" I was able to find, it may well be the BE200 card from Intel.

Unfortunately, we currently have no more detailed information on availability.