Here is my attempt :
a) 3^4 = 81 cards
b) 81C3 = 85320 sets of 3 cards
c) All different 3! *3!*3! = 216
d) Say they are all red and the other attributes are all different 3!*3!*3! = 216
But there are 12 different things that could be the same so that is 12*216 = 2592
e) exactly 2 matching atributes
Say they are all R1 they are each allotted a shape. then there is 3! choices for shading.
12C2 *3! = 66*6 = 396
f) say they are all the same except one is red, one Purple, and one green. There is one set of those.
So there is one set for each attribute. so that is 4