1. 4-digit numbers are to be formed using four of the digits 2, 3, 7, 8 and 9. Each digit may be used once only in any 4-digit number. Find how many 4-digit numbers can be formed if

(i) there are no restrictions,

[1]

(ii) the number is even,

[1]

(iii) the number is greater than 7000 and odd.

[3]