Discovery Exercise $4-3$ Estimated Time: $35$ minutes Objective: Compose file search commands. Description: Write the command that can be used to answer the following questions. $($Hint: Try each on the system to check your results.$)$ a$.$ Find all files on the system that have the word "test" as part of their filename. b$.$ Search the PATH variable for the pathname to the awk command. c$.$ Find all files in the $/$usr directory and subdirectories that are larger than $50$ kilobytes in size. d$.$ Find all files in the $/$usr directory and subdirectories that are less than $70$ kilobytes in size. e$.$ Find all files in the $/$ directory and subdirectories that are symbolic links. f$.$ Find all files in the