There are $11$ points in a plane,of which $5$ points are collinear. The total number of distinct quadrilaterals that can be formed with vertices at these points is:

Five boys and three girls are seated in a row at random. What is the probability that all three girls sit together?

$A$ polygon has $35$ diagonals,then the number of its sides is

There are $5$ points $P_1, P_2, P_3, P_4, P_5$ on the side $AB$,excluding $A$ and $B$,of a triangle $ABC$. Similarly,there are $6$ points $P_6, P_7, \ldots, P_{11}$ on the side $BC$ and $7$ points $P_{12}, P_{13}, \ldots, P_{18}$ on the side $CA$ of the triangle. The number of triangles that can be formed using the points $P_1, P_2, \ldots, P_{18}$ as vertices is:

$p$ points are chosen on each of the three coplanar lines. The maximum number of triangles formed with vertices at these points is

Seven white balls and three black balls are randomly placed in a row. The probability that no two black balls are placed adjacently equals