Among the top tennis strings on the market, nylon or polyester string is most often used. Nylon is used in so called monofilament strings; multi-filament feature nylon combined with strings such as polyester, Kevlar, Vectran, etc.
If you are talking about traditional ones, they most commonly consist of rubber, string, leather, and wood.
No, you do not have to be, you can live there or most commonly be a citizen.
It is most commonly made in flexible forms such as a chain, as a string of beads, pearls, gemstones, or other natural materials, or made of a more inflexible band of metal embellished with gemstones, pearls, beads,
You actually only need one piece of string to string a racquet. The string has to be about 10m long though! it all depends on what you are looking for from the string. The most you should use though is two, one for the main strings (lengthways) and one for the crosses.
According to the "Tennis Warehouse" (commercial) website (refer to the link, below), "natural gut" is made predominantly from cow intenstines, though sheep intestines were used early on. Since natural gut is very expensive, most players use strings made from artificial materials, such as nylon and other composite materials. Regardless of the source, the process to make strings is basically the same: The material is formed into a single strand via extrusion under heat and pressure, until it meets the requirements of the manufacturer for temperature, tension or torsion, density, gauge (thickness), etc. The string may be colored or left as is (i.e., "natural"). The manufacture will also stamp or laser imprint information about the string on the string itself; often it is so small, that most people aren't aware that it's there. The strands may be cut and packaged into "sets" (i.e., individual packets to string a single racquet, usually 40 feet in length) or "reels" (i.e., a single strand many yards in length which is meant to be cut for individual racquets, usually by a professional stringer). For further information, click on the Wikipedia link, below.
Rye is most commonly made into gbreqd, and then second commonly into cereals.
They are very important. The most commonly used functions are the string and file handling ones.
They are most commonly made of chitin
Tennis is definitely the most popular. There are differences between all the racquet sports.
Yes, it is legal to sell rudraksha. It is type of seed that comes from an evergreen tree and is often used to string for jewelry. It most commonly used to string prayer beads.
Most commonly corn or what.
Iron.