If four points are taken on each of three parallel lines in a plane,then the maximum number of triangles formed with these points is

How many triangles can be drawn by means of $9$ non-collinear points?

There are $16$ points in a plane out of which $6$ are collinear. How many lines can be drawn by joining these points?

Let $n > 2$ be an integer. Suppose that there are $n$ Metro stations in a city located along a circular path. Each pair of stations is connected by a straight track. Further,each pair of nearest stations is connected by a blue line,whereas all remaining pairs of stations are connected by a red line. If the number of red lines is $99$ times the number of blue lines,then the value of $n$ is:

In a plane,there are $37$ straight lines,of which $13$ pass through point $A$ and $11$ pass through point $B$. Moreover,no three lines (apart from the lines passing through $A$ and $B$) pass through the same point,and no two lines are parallel. What is the number of points of intersection of the straight lines?

What is the number of diagonals in an octagon?