Final answer:
The ML function definitions for the given functions are provided.
Step-by-step explanation:
1. The function definition for f(g,x,y) = g(x,y) is:
def f(g,x,y):
return g(x,y)
2. The function definition for f(g,h,x) = g(h(x)) is:
def f(g,h,x):
return g(h(x))
3. The function definition for f(g,x) = g(g(x)) is:
def f(g,x):
return g(g(x))