1st one is correct.

Last one will be 2*4*2*5*3 ways since burger can be chosen in 2 ways, cheese in 4 ways(3 types of cheeses; and also you may not want to take cheese. That is one more possibility), 2 types of buns, 5 toppings and 3 condiments.

Try to workout 2nd and 3rd problem on your own. See the 8th point. http://www.mathhelpforum.com/math-he...ng-151418.html