Date: Mon, 22 Nov 1999 21:20:30 -0600 From: Mike Openshaw <openshaw@airmail.net> X-Mailer: Mozilla 4.5 [en] (WinNT; I) X-Accept-Language: en MIME-Version: 1.0 To: hwang@phy03.phy.ntnu.edu.tw Subject: Thank you for the very useful site My son has just used your very useful site for a middle school paper on sound waves. He really enjoyed experimenting with the frequencies and studying the result. Never seen him enjoy science so much. Again, many thanks.