<p>Do not let the points at the beginning keep you from getting the points at the end.
If you can do part (c) without doing (a) and (b), do it. If you need to import an answer from part (a), make a credible attempt at part (a) so that you can import the (possibly wrong) answer and get your part (c) points. </p>
<p>What tacopaco said for the most part for AP Calc AB.</p>
<p>There are times where there are certain preconditions for being eligible for those answer points. For instance, with separable differential equations questions, if your answer was supposed to be exponential, your answer will likely have to be exponential to carry forward.</p>
<p>Also, generally speaking, if your answer is significantly simpler than the answer you’re supposed to get, you likely won’t get credit for the answers in later parts.</p>
<p>Yes, there is error carried over. But it is best not to make any mistakes in the first place, yes? If the error is so significant that it changes the latter parts of the problem completely, you will not be awarded points for error carried forward.</p>
<p>For Physics B, they don’t give you points for error carried over but for substitution. Substituting the right variables into an equation gives you points.</p>