A set of five possible wave functions is given below, where L is a positive real number. $1($x$)=$ Ae$-$x$,$ for all x $2($x$)=$ A cos x$,$ for all x $3($x$)=$ Aex, $0$ x L $0,$ for all other x $4($x$)=$ A$,-$L x L $0,$ for all other x $5($x$)=$ Ax$,$ x$$ L $0,$ for all other x Which of the five possible wave functions are normalizable? $($There may be more than one correct choice.$)1)$ A$)5($x$)$ B$)3($x$)$ C$)4($x$)$ D$)1($x$)$ E$)2($x$)$