Answer:
#3) 72; #4) 40,320; #5) 90.
Step-by-step explanation:
#3) The number of possible choices are found by multiplying the choices of flavors and the choices of toppings:
6*12=72.
#4) The ordering of 8 cards is a permutation, given by 8!=40,320.
#5) This is a permutation of 10 objects taken 2 at a time:
P(10,2) = 10!/(10-2)!=10!/8!=90.
P.S I had the same question once.