Algebra 2
posted by Tom .
Abelardo wants to create several different 7character screen names. He wants to use arrangements of the first 3 letters of his first name(abe, followed by arrangements of 4 digits in 1984, the year of his birth. How many different screen names can he create in this way?
A.72
B.144
C.288
D.576

The 'abe' can be arranged in 3! or 6 ways
the '1984' can be arranged in 4! or 24 ways
number of arrangements = ????
what do you think? 
It's 144