The structure of your if statements is incorrect. Try this:
if ( $w ( ‘#dropdown4’ ). value === ‘duplex’ ) {
$w ( ‘#group37’ ). show ();
$w ( “#group38” ). show ();
$w ( “#group31” ). collapse ();
$w ( “#group32” ). collapse ();
} else if ( $w ( ‘#dropdown4’ ). value === ‘triplex’ ) {
$w ( ‘#group37’ ). show ();
$w ( “#group38” ). show ();
$w ( “#group31” ). show ();
$w ( “#group32” ). collapse ();
} else if ( $w ( ‘#dropdown4’ ). value === ‘duplex’ ) {
$w ( ‘#group37’ ). show ();
$w ( “#group38” ). show ();
$w ( “#group31” ). show ();
$w ( “#group32” ). show ();
}