$10,000 a year
2.69 per mile
No, they are belt driven. That's how they operate.
Depends on what type of tractor and trailer you had in mind. For a farm tractor pulling a trailer, it's usually a pintle on the tractor which is run through a clevice on the trailer. For road going vehicles, the fifth wheel trailers are often used, where a trailer kingpin will be inserted and locked into a fifth wheel on the vehicle. In the case of an 18 wheeler, air lines will connect from the tractor to the trailer to operate the trailer's air brake system.
Depending on the make, the average length of a tractor is 22 feet. A standard trailer is 53 feet. The combined average length of the vehicle is 70 feet.
About £200
Around $60,000, and unless you work for a company you can't buy a separate trailer. $135,000 for a fullsize tractor, $72,000 for a reefer trailer.
The average tractor trailer holds almost 300 gallons of gas! I am unsure of if you were speaking of a tractor trailer or a tractor for cutting the lawn.
Bigger than average
The average length of a standard tractor trailer is 70 feet in all, the trailer itself being 53 feet in length. Most flatbed trailers are 48 feet long.
Four to nine MPG, depending on a number of factors. It's pretty much the same with any tractor trailer.
This site looks promising http://www.nexttruckonline.com/ they sell trucks, tractor trailers and accessories/maintenance items that you would need for your tractor trailer.
Whatever the company pays.