A photographer is arranging 3 puppies in a row for a photo. There is one black puppy (B), one tan puppy (T), and one white puppy
(W). Which list shows all the possible arrangements of the puppies? A:TWB, BTW, WBT
B: BTW, BBB, TTT, WWW, BBT, BBW, TTB, TTW, WWB, WWT
C: BTW, BWT
D: TWB, TBW, BTW, BWT, WBT, WTB
Since there are 24x-16 total and 3x-2 in each row, we can just divide it to get the number of rows. Since 24/3 and 16/2=8, which is very convenient, we can easily find the number of rows to be 8
