User talk:Dannyzf1234

September 2017
Hello, I'm Oshwah. I wanted to let you know that I reverted one of your recent contributions —the one you made with this edit to Mass–energy equivalence— because it did not appear constructive. If you would like to experiment, please use the sandbox. If you think I made a mistake, or if you have any questions, you can leave me a message on my talk page. Thanks.  ~Oshwah~  (talk) (contribs)   12:09, 13 September 2017 (UTC)