Eight points are marked on a straight line and nine points are marked on another parallel straight line. How many triangles can be constructed with vertices among the above points?
A. 252
B. 288
C. 540
D. 680
Answer:C
Eight points are marked on a straight line and nine points are marked on another parallel straight line. How many triangles can be constructed with vertices among the above points?
A. 252 B. 288 C. 540 D. 680