#### Answer

(a) There are 24 possible permutations.
(b) No

#### Work Step by Step

(a) First of all
Find $4P_{4}$
Write it by using factorials:
$4P_{4}=\frac{4 !}{4-4}!$
Simplify:
$4P_{4}=\frac{4!}{0!}=\frac{4.3.2.1}{1}$
$4P_{4}=24$
Thus, there are 24 possible permutations.
(b)
No, especially if your name is very short like in part (a) as it is more prone to hackers since there are only a number of possible passwords using your name.