Where have all the flowers gone, Pete?

Just where did folk singer Pete Seeger come up with the idea for that hammer song, anyway? Well, now you can submit that question and others to him directly -- electronically, that is. The PBS Engage blog is soliciting questions for the legendary troubadour and musical activist in honor of his 90th birthday concert on Great Performances Thursday night (check local listings) and throughout August. Lauren Saks, web producer and blogger for Engage, will choose five questions for Seeger to answer; responses will be posted next week.