1. When using a command line program, what is the purpose of the "pwd" command? A) Print working directory B) Present working directory C) Print work directory D) Present work directory Answer: A) Print working directory Rationale: The "pwd" command is used in command line programs to display the current working directory. 2. In shell programming, what does the "$$" variable represent? A) The process ID of the current shell B) The user's home directory C) The number of arguments passed to a script D) The exit status of the last executed command Answer: A) The process ID of the current shell Rationale: The "$$" variable in shell programming represents the process ID of the current shell. 3. Which shell construct is used to repeat a command a specified number of times in a shell script? A) for loop B) while loop C) until loop D) select loop Answer: A) for loop Rationale: The for loop in shell scripting is used to iterate over a list of items a specified number of times. 4. In a shell script, which command is used to define and call a function? A) func