Is "Gern" in suggesting Trini Lopez for #3 getting muddled up with "If I had a hammer" the old Weaver's song that was later recorded by PP&M and later very successfully by Trini Lopez.
#11 ... The first I remember this one was by The Kingston Trio in the 50's .. I don't remember anyone else doing it as a single. It was on LP by PP&M and no doubt others too.