Which command will display the value of a variable named TMPDIR?

The command that will display the value of a variable named TMPDIR is echoTMPDIR.Theechocommandwillprintitsargumentstothestandardoutput.Thesign is used to reference the value of a variable in bash. If you omit the $ sign, echo will print the name of the variable instead of its value. If you use single quotes around the variable name, echo will also print the name instead of its value. If you use double quotes around the variable name, echo will print its value as expected. References:https://documentation.suse.com/sles/15-SP3/html/SLES-all/cha-bash.html#sec-bash-variables