7 points are marked on a straight line and another 4 points are marked on a second straight line with no points in common. How many triangles can be constructed with vertices from among the above points?
Choose the correct choice from the following answers
A) 91
B) 126
C) 196
D) 21
E) 14
getting the answer 126 which is not in the choices, what is the source of the problem?   7C2* 4C1 + 4C2* 7C1 = 126   126
<result>B</result>
7 points are marked on a straight line and another 4 points are marked on a second straight line with no points in common. How many triangles can be constructed with vertices from among the above points?