How could you check the existance of a key in a Hash in Perl?

%FM = ( 'Radio City' => 91.1,
              'Big FM' => 92.7,
              'Red FM' => 93.5,
              'Radio One' => 94.3,
              'Radio Mirchi' => 98.3,
              'Fever' => 104.0,
              'Oye FM' => 104.8,
              'FM Rainbow' => 107.1,
              'FM Gold' => 100.7);

if (exists ( $FM { "Fever" } ) )
{
    print "Frequency of FM Fever is $FM{Fever}MHz.\n";
}