solution: Each of the five marked angles measures $360/5=72$ degrees, so $\boxed{72}$ degrees is the minimum angle through which the pentagon may be rotated so that it coincides with its original position.
  
  [asy]
  size(150);
  defaultpen(linewidth(0.7));
  int i;
  for(i=0;i<=4;++i)
  
  {
  draw(origin--dir(18+72*i)--dir(18+72*(i+1)));
  draw(anglemark(dir(18+72*i),origin,dir(18+72*(i+1)),3+fmod(i,3)));
  }
  [/asy]
prompt.content: <|im_start|>system
  You are a helpful assistant.<|im_end|>
  <|im_start|>user
  A regular pentagon is rotated counterclockwise about its center. What is the minimum number of degrees it must be rotated until it coincides with its original position?
  Please reason step by step, and put your final answer within \boxed{{}}.<|im_end|>
  <|im_start|>assistant
  
prompt.role: user
extra_info.answer: 72
extra_info.question: A regular pentagon is rotated counterclockwise about its center. What is the minimum number of degrees it must be rotated until it coincides with its original position?
extra_info.split: test