The initial paragraph in the Jennings text discussion under the heading "The Uniform Commercial Code," p. 370, details the how and why of the Uniform Commercial Code, i.e., previously, most contracts lacked uniformity because they fall within the purview of common law (which is really anything but " common") of the various states (as mentioned in one of Module 3's Web Search activities).
As you might therefore expect, we will once again be turning to state laws in the interest of exposing you to the diversity of how states organize their laws and related Web resources.
Using your Web browser, and the methodology explained last week for trying to access state statutes, i.e. the "state.??.us" approach: Use the state of California and provide its citation(s) that equate to the "Section 1-303. Course of Performance, Course of Dealing, And Usage of Trade" which define what those terms mean.
Two other aspects of that search should be clarified. First, the word "citation(s)" was purposefully used because I am aware that one or more states have divided these subjects into more than one section, so there may be more than one citation. Second, you will notice that this section had a different designation in the initial, as opposed to the revised, UCC.
Therefore, don't be surprised if you find a state's provision in either Part 1 or Part 2 of the UCC. Finally, the state's UCC will most likely have a hierarchy of these provisions, i.e., course of dealing, course of performance, usage of trade.
Provide the hierarchy, i.e., order of precedence, and the citation(s) for that order.