$85.$ Choose the condition that must be specified in order to liquify CO$2($triple point for CO$2$ is $-57\backslash$deg C and $5\mathrm{.}2$ atm$).$

Pressure must be kept below $5\mathrm{.}2$ atm

Temperature must be kept above $-57\backslash$deg C

Pressure must be kept below $5\mathrm{.}2$ atm. and temperature must be kept above $57\backslash$deg C

Pressure and temperature must be kept below $5\mathrm{.}2$ atm. and $-57\backslash$deg C respectively