Question: Suppose that f is a function from the set A to the set B. Prove that
a) if f is one-to-one, then Sf is a one-to-one function from P(A) to P(B).
b) if f is onto function, then Sf is an onto function from P(A) to P(B).
c) if f is onto function, then Sf -1 is a one-to-one function from P(B) to P(A).
d) if f is one-to-one, then Sƒ -1 is an onto function from P(B) to P(A).
e) if f is a one-to-one correspondence, then Sƒ is a oneto-one correspondence from P(A) to P(B) and Sƒ -1 is a one-to-one correspondence from P(B) to P(A).