Let us consider the following expression tree.

Select one or more:

a$.$ The postfix notation is $fe\frac{c}{{?}^{*}}dh++$

b$.$ The postfix notation is $)h+{?}^{*}+$

C$.$ The postfix notation is $f+e\frac{c}{{?}^{*}}dh+$

d$.$

The infix notation is: $\frac{f+e}{c}*(d+h)$

e$.$ The postfix notation is $fe\frac{c}{d}h+{?}^{**}+$

f$.$ The infix notation is: $f+\frac{e}{c}*(d+h)$