<p>On the Course Reader is says, due Wednesday, “PF 22-25” and “CS 19-27”. What the heck do PF and CS mean?</p>
<p>I’m assuming those are the readings required and not the homework to be turned in. </p>
<p>I don’t have my course reader anymore but from the homework assignments list I saved from when I took the course, PF refers to “The Cosmos”, the textbook by Pasachoff and Filippenko (hence PF). </p>
<p>Not sure about CS, but it’s probably class slides (included in the course reader). </p>
<p>Numbers after PF and CS should be page numbers and slide numbers respectively.</p>
<p>Ohhhh, I just checked the course reader and you’re right; to the top left of every slide is CS followed by a number. And, PF as the Cosmos book sounds right 
Thank you so much!!!</p>