Question

Dustin has a set of 180 distinct blocks. Each of these blocks
is made of either wood or plastic and comes in one of three sizes
(small, medium, large), five colors (red, white, blue, yellow,
green), and six shapes (triangular, square, rectangular, hexagonal,
octagonal, circular). How many of the blocks in this set
differ from
a) the small red wooden square block in exactly one way?
(For example, the small red plastic square block is one such
block.)
b) the large blue plastic hexagonal block in exactly two
ways? (For example, the small red plastic hexagonal block
is one such block.)