there are 10 points on a plane ,and any arbitrary three points are not in a straight line.segments or not,linking any two points .In order to make sure that any point in these ten points can arrive at any other points by the linking line segments,how many line segments between two points should be linked at least?不是翻译，是做题，不用英语回答。

there are 10 points on a plane ,and any arbitrary three points are not in a straight line.
segments or not,linking any two points .In order to make sure that any point in these ten points can arrive at any other points by the linking line segments,how many line segments between two points should be linked at least?
不是翻译，是做题，不用英语回答。