Thirteen persons are sitting in a row. Number of ways in which four persons can be selected so that no two of them are consecutive is equal to ____

number of ways in which all the letters of the word “M A R R I A G E” are permutated if no two vowels are never together.

number of numbers lying between 100 and 1000 using only the digits 1,2,3,4,5,6,7 without repetition.

number of ways in which 4 alike chocolates can be distributed among 10 children so that each child getting at most one chocolate.

number of triangles can be formed by joining 12 points in a plane, of which 5 are collinear