<p>A swimmer wants to cross a river from point A to point B. Line AB makes an angle of&nbsp;<span class="equation">\(30^0\)</span> with the flow of river. Magnitude of velocity of the swimmer is same as that of the river. The angle&nbsp;<span class="equation">\(\theta\)</span>&nbsp;with the line AB should be _________<span class="equation">\(^0\)</span>, so that the swimmer reaches point B.</p>

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