User talk:99.203.29.174

Hello, I'm David Eppstein. I wanted to let you know that one or more of your recent contributions to Ruled surface have been undone because they did not appear constructive. If you would like to experiment, please use the sandbox. If you have any questions, you can ask for assistance at the Teahouse. Thanks. —David Eppstein (talk) 07:52, 30 May 2020 (UTC)