Didn't you ever use MATLAB in your linear algebra course? YOu should have taken that course before taking signal processing. If you did not, stop trying to do the problem and sit for a while learning how to use MATLAB. The questions it is asking you are very basic functions like graping and solving matrixes. If you spend some time learning how to use MATLAB rather than worrying about how to do the problem you will probably make better progress. Ask your professor or lab instructor for help.
Just so you know, my MATLAB assignments for signal processing (discrete tiem signals at least, I forget about continuous time) often took me 5-6 hours to finish. If it's just graphing stuff you should be able to finish that in your 3 hour lab. Just ask the TA for help. They usually give you tutorials and reading material on the commands needed for the lab, rather than just handing you the page.