17 and 18 are also quite easy to do. The picture of 18 is not very beautiful, but it looks simple.
19' s question is so stupid, it's killing me ... but I did it right-
20 problems of conic curve, especially the conventional simultaneous direct solution.
I didn't do the second question of 2 1, and I really can't do it.
Choose one from three, and polar coordinate 23 questions are particularly easy to do.
So I can probably get 140 = =