The greatest number is six.
The greatest number of intersection points with just four lines is 6.
A sphere.
7
10
The greatest number is six.
The greatest number of intersection points with just four lines is 6.
None of them.
A sphere.
7
10
16
A circle has an infinite number of lines of symmetry, corresponding to any of its diameter lines, to any arbitrary level of division (degrees, minutes, seconds).
100*99/2 = 4950
FRACTION
four
depends on the position of the points if points are collinear, we have just only one line, the minimum number. If points are in different position (if any of the two points are not collinear) we have 21 lines (7C2), the maximum number of lines.