math
posted by Ele .
pepi's pizza has a choice of thin crust or thick crust. The available toppings are mushrooms, onions, pepperoni and sausage. Make a tree diagram showing the possible outcomes for a 1 topping pizza.

Here are examples of tree diagrams.
http://www.google.com/search?q=tree+diagram&hl=en&prmd=imvns&tbm=isch&tbo=u&source=univ&sa=X&ei=5CSfT_TIJqH62AWWoMSODw&sqi=2&ved=0CDMQsAQ&biw=711&bih=453 
And the rest of the question?