If $^{12}P_r = 1320$,then $r$ is equal to

In how many ways can a girl and a boy be selected from a group of $15$ boys and $8$ girls?

In how many different ways can the letters of the word '$BANKING$' be arranged so that the vowels always come together?

The sum of the divisors of $2^5 \cdot 3^4 \cdot 5^2$ is

There are $16$ points in a plane,no three of which are in a straight line except $8$ which are all in a straight line. The number of triangles that can be formed by joining them equals

There are $5$ apples,$4$ mangoes,$3$ oranges,and $1$ each of $2$ other varieties of fruits. The number of ways of selecting at least one fruit of each kind is