Yes.
It stands for "12 volts, direct current".
Almost all cars in NZ have 12VDC electrics. Most portable generators which produce 230VAC, will also have a 12VDC accessory output for battery charging, etc. There are no general reticulations of 12VDC.
850va 12vdc inverter transformer praemari tans
In general no, it might do some damage to both the equipment and the power supply. In certain specific cases it might be all right if you are able to measure the current to make sure it is 500 mA or less, and you can also ensure that the appliance can withstand 15 v.
Yes.
From what? If you need 12VDC for temporary use, there is a very good 12VDC source in your PC power supply.
If you know what you're doing, you can probably accomplish that in a 1A circuit.
Probably not. The other way around would be fine: a device that only needs 750mA will work fine on a 2A power supply, but one that needs 2A will NOT work on only 750mA, which is less than half the current required.
Yes - it will just take a little longer to charge the device.
To convert 12VDC to 120VAC at 9.5A, you will need a minimum of 95A of 12VDC current. This calculation is based on the premise that power remains the same in both systems (P=VI), ignoring inefficiencies and losses in the conversion process.
Most all are 12vdc