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use variables already defined.
5) The answer itself also needs one tweak–unlike in NFR where the actual answer or variable is identified as ans1 (ex: ans1=@a1), for multiple choice define ans1 as the answer choice that has the correct variable listed as the solution among the multiple choice boxes (ex: ans1=1 , where \choice{}{1}{@a1}).
t = omega*2.0*pi/60.0/alpha;
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In multiple choice the ans1= in the code box has to be the choice with the correct answer (ie, ans1 = 1; instead of ans1 = a1;), not what's being called (which is vastly different than free response).
If you're getting 'tex validation errors' please check that ans1 = a choice number instead of a variable.
Pro tip: just make a precursor ans = expression on how to calculate the answer. In the upper TeX box, in choice 1 put in ans, and in the bottom Code box, ans1=1.
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