Repetitions and Derangements

Problem 1:

1. In how many ways can 5 red checkers and 12 black checkers be placed on squares of a standard 8X8 checkerboard?
2. A farm stand wants to make a display with 20 pieces of fruits or vegetables. Assuming that they have 16 different kinds of produce and a large amount available of each type, how many ways are there for them to make a display? How would your answer change if you want at least 3 pumpkins included in the display?
3. In how many ways can the letters in the "word" LLAMAALPACA be arranged?