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<li><p>You are essentially required to take calc and bio. All others are optional. You should take at least one language placement, if you can. </p></li>
<li><p>It deals with essential material in basic ways. The last questions are difficult unless you’ve studied those concepts, in which case they’re not very hard. It’s meant to show how much math you’ve done and which class you’d be most ready for during the year.</p></li>
<li><p>That’s not true. Honors Calculus is always difficult (I’m not even going to get into Honors Analysis because you seem to only be asking about calc)–reviewing material makes no difference at all since it’s an entirely proof-based curriculum. The 130s are usually thought to be like BC Calc, and the 150s are a level above that. I took 153 autumn quarter (the placement was 153, strongly urged to take 160s; it’s a common placement for students who got 5s on BC Calc), and it was fine. I didn’t get a very good grade, but I did almost no work for the class and didn’t pay attention. 
Most people find their math classes fine, especially after the masses of students drop down from 161 to 153 second week of the quarter. But, yeah, don’t prep. The placement will place you where you ought to be.</p></li>
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