Is liquid nitrogen is same as nitrogen?

Indeed it is, in the very same way that ice is the same as water. Liquid nitrogen is nitrogen, but in a much colder state than the usual gas.

Nitrogen only remains a liquid at very low temperatures (-196oc) above this temperature the liquid will return to a gas, so warm it us is the answer, although because of the extreme cold temperatures...

no. Compressed nitrogen need not be insulated. Liquid nitrogen is always insulated. Typically compressed nitrogen is stored at high pressure(over 1000 psi) and liquid nitrogen is kept at less than...

It has to be cooled to below -196 degrees Celsius or -321 degrees Fahrenheit.

Nitrogen becomes a liquid when it is cooled to below -196 °C (-321 °F).(The industrial production is by liquefying air, then separating the nitrogen.)