That depends on the wire's insulation and the temperature rating of the devices you're connecting it to. This type of question usually means you aren't ready to do this yourself. Study some electrical material and the National Electrical Code and work this answer out for yourself, or call a professional electrician. If I were to give you an answer, you might attempt to do something you shouldn't be doing, and that may cost someone a shock, a home fire, or their life. At least see the applicable Article in the NEC, 310.16.
A 100 amp service requires that you use AWG 4 copper wire or AWG 2 aluminum wire.
A 350 MCM copper conductor with an insulation rating of 90 degree C is rated at 350 amps.
When you talk of voltage, you should be thinking of the insulation factor of the wire. By the same token when you talk of wire size, it is based on the amperage the wire is required to handle.
You need to know the amperage to size the wire. For 220 V at 20 A you would need 12 AWG. At 220 V at 30 A 10 AWG.
2 AWG.
The maximum amperage rating for an 18 AWG wire is typically around 16 amps.
Copper or aluminum AWG. As for gauge and such, it depends on how much amperage you have running through it, and the length of wire.
I would recommend you use AWG # 2 copper or AWG # 1/0 aluminum for that distance and amperage.
The amp rating of an 18 AWG wire is typically around 16 amps.
The ampacity rating for 18 AWG wire is typically around 16 amps.
The current rating of an 18 AWG wire is typically around 16 amps.
The amp rating for 18 AWG wire is typically around 16 amps.
The amp rating for a 10 AWG wire is typically around 30-40 amps.
The amp rating of 10 AWG wire is typically around 30 to 40 amps.
The maximum current rating for an 18 AWG wire is typically around 16 amps.
The maximum current rating in amps for a 10 AWG wire is typically around 30 amps.
AWG # 6 copper or AWG # 4 aluminum