<p>masamune’s right - 200/201 is a 2-semester course, with 200 only offered 1st semester and 201 only offered 2nd semester… this is why it’s difficult to start the physics sequence second semester: you have to start in the second half of the course.</p>
<p>and yup, just for general reference, “a” designates a course as first semester, “b” as second semester.</p>