The topic score is 10, and the college entrance examination will follow the principle of grading step by step. According to your idea, first convert point P into a linear equation of one variable and find out the rectangular coordinates of the center of the circle, then find out the rectangular coordinate equation of the circle and finally convert it into polar coordinates. Based on this idea, the first step is correct, starting with finding the rectangular coordinates of the center of the circle, and making mistakes constantly. Personally, I think it would be more appropriate to give 2~3 points. Of course, it depends on your writing format and size. If you write clearly and have key formulas such as changing polar coordinates into rectangular coordinates, your score may be higher, but it is unlikely to exceed 5 points. All things considered, I still think 2~3 minutes is more appropriate.