let $l,m,n$ be the 3 regular expressions. consider the following identities.
$1.( l^*m^*n^*)^* = (lm^*+mn^*+nl^*)^*$
$2.(mn+m)^*m = m(nm + m)^*$
$3.(l^*m^*n^*)^* = (l^* + m^*n + n^*)^*$
$4.(l^*m)^* = (l+m)^*$
how many of the above identities are correct?