First of all, me and my wife are monogamous and married for 8 years, so the std risks are none, but I find little information on this. Me and my wife have anal sex at least weekly and she wants me to pee in her butt after I finnish to see how it feels but we cant find any health risks or concerns on this matter other than a few references to people doing it. Is there major risks or just the regular anal sex risks?
Yes it is possible to make mathematical models of stars. I don't understand your additional details as your English grammar is too poor to comprehend. Perhaps you should post in your native language in the appropriate language forum or ask a native English speaker who knows your language to translate for you. Sorry I can't be more help.
The solder used for copper plumbing work has lower lead than in the past. It's safe to use otherwise some idiot would have made yet another law prohibiting the use. If you really don't want anything like that in your water system then go with the various plastic solutions and clamp-on fittings. That way you won't have any issues with lead. It is also simpler to do and will likely be less expensive than copper pipes.
