Ex10 14

$\def\abs#1{|#1|}\def\i{\mathbf {i}}\def\ket#1{|{#1}\rangle}\def\bra#1{\langle{#1}|}\def\braket#1#2{\langle{#1}|{#2}\rangle}\def\tr{\mathord{\mbox{tr}}}\mathbf{Exercise\ 10.14}$

Show that the four Bell states $\ket\Psi^\pm$ and $\ket\Phi^\pm$ are all LOCC equivalent.