[SOLVED] Combination/probability help please

! need a refresher on this I cant find my notes and my profestor is no where to be found any help is apreciated ^ ^

1)if you are recieving 8 books as gifts and there are 27 different titles how many possible selections are there if each title can only be used once?:

the way I remember it you should set it up like this if g=gift

g27

g26

g25

g24

g23

g22

g21

g20

only thing is do I multiply those or add or what? also if anyone knows how it would be entered on a TI-83 plus that would help as well

2)If a fair die is rolled what is the probability that the number rolled is 5 given that it is odd

P= favorable/total outcoms p=1/6 also does the given it is odd part have any effect on the problem or is it extra info?

3)resteraunt offers 3 types of lettuce 5 toppings and 6 dressings in a salad how many combinations are there asuming only one toping letucce and dressing can be chosen

S T5 D6 6x5=30 30x3=90 ans=90