Any of these may be things you work on outside of class. The instructor will expect you to understand the ground rules for working on the assignment, and to follow them. If the rules for an assignment are unclear, it is your responsibility to ask the instructor. Plagiarism is the act of using someone else's work without giving them credit for it, even if you do so with their permission. Plagiarism and not following the ground rules for an assignment are violations of the Gentleman's Rule.
Linear algebra is a prerequisite for most of the mathematics courses beyond calculus.
If you plan to take more mathematics, you should spend some time carefully thinking about which courses you want to take and in which order. You should also check out the information for mathematics majors and minors through the department web page. Majors should eventually have someone in the department as their advisor, certainly by the end of your Sophomore year. See the department web page for more information on this and other neat stuff. Out of courtesy to your instructor and classmates, please don't use tobacco products during class .