Hi I really need help with the following questions. Thanks

1. (a) How many different numbers of 4 digits may be formed with the digits 0,1,2,5,6,7,8 if no digit is used more than once in any number?

(b) How many of the numbers formed in (a) are even?

2. There are 6! Permutations of the 6 letters of the word "square"

(a) In how many of them is "r" the second letter? _ r _ _ _ _

(b) In how many of them are "q" and "e" next to each other?