Although I have not given this Exam, Still trying.
Statement 1- False.
Reason- Number of one one function from set A containing n elements to set B containing m elements is mpn.
ATQ- npn= n!.
Statement 2- True.
Suppose domain and codomain is set of all integers (Z). Then
ATQ- Z^Z -----> Z^Z is same / equivalent to Z ------> Z. [ as integers are closed under multiplication ].
It will be bijective.
Statement 3- False.
Counter Example-
A= {1,2}
B= {3,4,1}
C= {1,3,5}
D= {2,5,3}
So, LHS evaluates to {1,2,3}
Ans RHS to { 1,3,5}.
So LHS # RHS.
FEEL FREE TO CORRECT!