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

$A$ father with $8$ children takes them $3$ at a time to the Zoological gardens,as often as he can without taking the same $3$ children together more than once. The number of times each child will go to the garden is

$A$ parallelogram is cut by two sets of $m$ lines parallel to its sides. The number of parallelograms thus formed is

The number of ways in which the letters of the word $TRIANGLE$ can be arranged such that no two vowels occur together is

Out of $7$ consonants and $4$ vowels,how many words of $3$ consonants and $2$ vowels can be formed?

The number of words that can be formed using the letters of the word $ARTICLE$,such that the vowels occupy even places,is