HTML PROGRAMMING

The code below is one of several trivia quizzes I've been tasked to solve. It contains a multiple choice questions with accompanying options. Which of the lines of code contains the answer and how are you able to arrive at that result?
PS: I'm new to HTML. This is more like a welcome assignment that was given to me.

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<h4>Question text</h4>
<input name="q74503:9:sequencecheck" type="hidden" value="1" />
<div>A triangular piece of land has two sides being 100m each with an angle of 30 degrees between them. If these two sides were measured with an error of 0.1m each but the angle was error free, what is that absolute error in the length of the third side?</div>
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<div><input name="q74503:9answer" type="radio" value="0" />
<div data-region="answer-label">a.
<div>0.816Cos75</div>
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<div><input name="q74503:9answer" type="radio" value="1" />
<div data-region="answer-label">b.
<div>0.05/Sin45</div>
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<div><input name="q74503:9answer" type="radio" value="2" />
<div data-region="answer-label">c.
<div>0.05/Sin75</div>
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<div><input name="q74503:9answer" type="radio" value="3" />
<div data-region="answer-label">d.
<div>0.816Cos45</div>
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<div><input checked="checked" name="q74503:9answer" type="radio" value="-1" /><label for="q74503:9_answer-1"><a tabindex="-1" href="#">Clear my choice</a></label></div>
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<div><input name="previous" type="submit" value="Previous page" /><input name="next" type="submit" value="Next page" /></div>

<input name="attempt" type="hidden" value="72449" /><input name="thispage" type="hidden" value="1" /><input name="nextpage" type="hidden" value="2" /><input name="timeup" type="hidden" value="0" /><input name="sesskey" type="hidden" value="ZbbeLnwiY2" /><input name="scrollpos" type="hidden" value="" /><input name="slots" type="hidden" value="4,9" /></p>
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Network connection lost. (Autosave failed).</p>
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