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# Choose the condition that must be specified in order to liquify CO2 (triple point for CO2 is - 57°C and 5.2 atm).

Pressure must be kept below 5.2 atm

Temperature must be kept above - 57°C

Pressure must be kept below 5.2 atm. and temperature must be kept above 57°C

Pressure and temperature must be kept below 5.2 atm. and - 57°C respectively