There is a 25 sided polygon (not necessarily regular) inscribed in a circle. The maximum number of pentagons that can be made by using the vertices of the polygon is ? The maximum number of octagons that can be made by using the vertices of the polygon such that `A_5, A_8& A_13` are never used while `A_10 and A_20` are always used is ? The maximum number of triangles that can be made by using the vertices of the polygon such that there are atleast two but unequal number of vertices of the polygon between any two vertex of the triangle