<PRE><B>Question 1159896</B>
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This question is from the series &amp;nbsp;&quot;Whether you know basic definitions&quot;.


I know them, &amp;nbsp;but the question is intended to check &amp;nbsp;YOUR &amp;nbsp;knowledge - not my.


Therefore, &amp;nbsp;I will not disclose the solution to you: 


&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;the University student must learn the definitions on his (or her) own.



The solution literally &amp;nbsp;&quot;swims&quot; &amp;nbsp;on the surface in front of you.



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