Which are possible correct commands to add two numbers? Select all answers that apply.
A. expr 2 + 3
B. echo expr 2 + 3
C. let x=( 1 + 2 ); echo $x
D. echo (expr(2 + 3))
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What commands are used to write the output of the free command to /tmp/free.out? Select all answers that apply.
A. free >> /tmp/free.out
B. free
C. free > /tmp/free.out
D. free
Which of the following parameters contains the name of the script being executed?
A. $n
B. var
C. $0
D. $*
Which of the following supplies the correct syntax to declare the function named showpath?
A. showpath [echo $PATH]
B. showpath {echo $PATH}
C. showpath () {echo $PATH}
D. showpath (echo PATH)
If you want to substitute the result of an expression (say echo /tmp) to be the argument for cd, how will you represent them? Select all answers that apply.
A. cd `echo /tmp`
B. cd (echo /tmp)
C. cd echo /tmp
D. cd $(echo /tmp)