There is also the subscription service of Skype that will let you call/receive calls to/from cell phones and other landlines - it's around $10 a month.
It's unusual for a cable to just go bad - unless somebody messed with it. Sounds more like an amp problem - a filter capacitor has died amongst other things.
Generally, a headlight, a tail light, one mirror, the muffler silenced, and a functioning front and rear braking system.
See your state's department of public safety website for specific information.
You need the correct voltage and the correct current (amps) from your adapter.
Look at the old adapter - it will say what the current output is (e.g., 2 AMPS).
Recommend you read up on what a modulator/demodulator does. It will explain how digital signals are embedded into analog signals.
The higher the frequency, the larger the bandwidth, the larger the bandwidth, the more data that can be transferred.
Depends on the highway, particularly if it has a minimum speed requirement. Signs are usually posted that say no bikes or any vehicle that can't do the minimum speed.