How to Find cardinality of $|\{f|f:A \to P(A) \}|$ if $|A|=a$ (A infinite set)

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Let A infinite set

$|A|=a$

$B=\{x|x \in P(A)\}$

$C=\{f|f:A \to P(A)\}$

$F=\{$ Set of all the relations on $A \times B \}$

$H=\{g|g:B \to B \}$

1) Find $|C|$

2)Find $|F\times H|$

for (1) i think $|P(A)^A|= |P(A)|^{|A|}=2^a$ is that correct and how to find (2)

thanks

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Obviously $|C|=|F|$.

The number of function from one element of $B$ to all the elements of $B$ is $2^{a}$. It means that $|H|=(2^{a})^{2^{a}}$.

These are the solutions: $$|C|=2^{a}*a$$ $$|H \times F|= (2^{a})^{2^{a}}*|F|= (2^{a})^{2^{a}+1}*a$$

These solutions consider all types of function.