An eight-digit number divisible by $9$ is to be formed using digits from $0$ to $9$ without repeating the digits. The number of ways in which this can be done is: (in $(7!)$)

How many numbers greater than a million can be formed with the digits $2, 3, 0, 3, 4, 2, 3$?

There are $16$ points in a plane, out of which $6$ are collinear. How many lines can be drawn by joining these points?

In how many different ways can the letters of the word '$THERAPY$' be arranged so that the vowels never come together?

From a group of $7$ men and $6$ women,five persons are to be selected to form a committee so that at least $3$ men are there in the committee. In how many ways can it be done?

In an examination hall,there are $4$ rows of chairs. Each row has $8$ chairs,$1$ behind the other. There are $2$ classes sitting for the examination with $16$ students in each class. It is desired that in each row,all students belong to the same class and that no $2$ adjacent rows are allotted to the same class. In how many ways can these $32$ students be seated?