3/6. overload is a module which isn't allowed (though there are ways to circumvent that), but more importantly bless is explicitly forbidden by the rules

the others look good :-)

UPDATE Re 9: it really is q, not qq. (notice the eval? :-)

UPDATE 2 As Roy Johnson pointed out, your 3b currently doesn't work (it's only a small one-char mistake though)

UPDATE 3 Your 9a doesn't work, they print differently but compare numerically equal. make sure to test your answers with perl -e '......; eval(q[$$foo]) != eval(q[0+$$foo]) or die' rather than using print, to avoid traps like these :-)

UPDATE 4 ex 11 works.. note that you can place it in front by using glob-assign

UPDATE 5 strictly speaking the semi isn't needed to make the condition true (which is the exercise), but even if you do include it it's still possible by dropping the "" from the sub