Subject: Lens/mirror Date: Fri, 03 Apr 1998 16:16:37 -0600 From: Kelly <> To: Mr. Hwang, I want to say that your virtual lab was unbelievably helpful to me. I attend the university of wisconsin-madison and I was having problems with optics concepts. I went under the internet and searched under lens and mirrors and fell upon your lab. I am very grateful. I was a little upset last night when I wanted to access the lens mirror applet, because I couldn't find it. I guess even the virtual labs have hours of availability. I guess that's my only suggestion, which isn't a very necessary one to attend to when most of us can access it during the day. Thanks again, Chris