Files are in the working directory
 

$ l s
Intro notesb ref2 section1 section3 section4b
notesa refl ref3 section2 section4a sentrev
Give commands for each of the following, using wildcards to express file names with as few characters as possible.
a. List all files that begin with section. b. List the section1, section2, and section3 files only. c. List the intro file only. d. List the section1, section3, ref1, and ref3 files.

Is this a homework question? Show us that you've at least tried.... examples...

a. this is homework
b. surely you listen at least some of the time in class?? This is a very basic concept