User talk:74.207.138.50

April 2020
Hello, I'm Pdcook. I wanted to let you know that one or more of your recent contributions to Chemical substance 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. P. D. Cook Talk to me! 20:27, 1 April 2020 (UTC)
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