To set a new code for her phone Ms. Lawson is using 5 digits. A/5

a) How many possibilities are there?

b) How many ways are there if she ends with the number 5 and no repetition?

c) How many ways are there if the number must be even and no repetition?

d) How many possibilities are there if the number must be even, not start with the number 2

and has no repetition?