Answer: She could create 60 platters.
Step-by-step explanation:
Given: A salad bar offers vegetable platters in 4 sizes (small, medium, large, and super-sized) and 6 different vegetables to choose from.
Number of combinations of selecting <em>r</em> things from <em>n</em> things is given by:-

So, the number of combinations of selecting 2 different vegetables from 6 = 
Now, By Fundamental counting principle, the number of different platters she could create = (number of ways of selecting 2 different vegetables from 6) x (Number of sizes)
= 15 x 4
= 60
Hence, she could create 60 platters.