The first thing you would do is state what 'this' source is.
is the internet a better news source than the television
The evidence might be unreliable because technology and other knowledge has advanced since that time, and their evidence might have been biased.
No, but if you download Plants VS Zombies Plus 4 Trainer from an unreliable source, you might want to have AntiVirus.
Information that you can trust would be termed reliable. If you aren't sure of the source, or the source is someone that you don't trust, then the information would be unreliable, and you wouldn't count on it in an important situation. If the information is reliable, then you might trust it without doing your own research.
slow, might be unreliable
unreliable
unreliable
Because they do not already have an internet source. The cost to connect a PS3 to the internet is only in the hardware that you might need to Purchase (router, ethernet cables, etc) if you do not have a WiFi connection, once a person already has the internet. The PlayStation Network does not charge for internet service, but you must already have the internet.
The internet can provide a lot of help for self-diagnosis (but nothing online should be considered a professional diagnostic tool and if you are truly concerned and are not sure what to do, a visit to your general physician or a kinestesiologist might be in order). Physiobench.com and WebMD.com are two sites that might be helpful in determining which injury is most likely in your case.
A primary source might be a letter, photograph, or speech that
I think so. Yes, but it could be unreliable at times because anyone could answer. And you might not get an answer at all.