<p>Even though general relativity is usually considered graduate-level in the US, I am the only graduate student in my own GR class, which is an upper-division elective; the instructor made it clear at the beginning of the semester that undergrad vs. grad was not important in assigning letter grades at the end of the semester in my case. However, that means the passing grade in absolute terms is higher since a B- is the passing grade in grad school (70% vs. 50%, which is a D)…</p>