Impurities

Q: My maid mopped over my baby urine by mistake and she continued to mop with the same water in other rooms too. Now what should I do? Shall I mop 2 times again?

Q: In my office washroom, the janitors keep the floor dry using a mop. Now the toilets are separate from the area where there are wash basins. However, the janitors use the same mop to clean the floor of the entire washroom (toilet and the washbasin area). Now when washing myself or performing wudoo at the wash basins, drops of water usually fall down on the floor. Does these drops become napaak after splashing from the floor? In the start I tried to avoid these drops from falling and then bouncing on my feet and clothes, but it is almost impossible and every now and then I get water splashed on my feet and clothes. What I should do in such a case? If I become napaak, how can I perform salah then because I have no way to change my clothes in the office and it happens too frequently?

Q: Is it mentioned in a Hadith that in order to purify a najis object it should be with running water?

Q: Please may the general ruling on 'circumstantial evidence' relating to the Soor (leftover) of animals be explained. I heard an example of a bowl of milk and a dog, but I cannot remember the particulars. We have cats at home and I am unsure when to consider something pure or as makrooh soor (leftover). If appropriate, please may the milk/dog example also be given.

Q: Is it permissible to tan elephant skin?

Q: I am currently abroad and I have been doubting everything recently. I was recently told that theres a potential of lard (pig fat) being used in the making of bread here in some of the bakeries. My friends eat that bread because they are non Muslims.

My question is, if they were to eat the bread which is a dry entity and then touch me with it after they are done, would I become najis, or does impurity only travel through wetness? 

Q: I had an infection on my toe which I washed off (whatever was coming out of the infection) in the tub. A little later, while the tub was still wet, I was making wudu in the tub and some water splashed back to me when I washed my face. Was this water impure? Also, when I am filling up a jug to use to make istinja, I sometimes place my finger in the water to check how warm it is. Does this affect the ability of the water to purify?

Q: I read in Bahisti Zewar under miscellaneous masa'il that if a person uproots his hair, then the root of that hair is regarded as impure because of the stickyness that is found on it.

1. Does this mean that if you uproot a hair anywhere on your body then the root of that hair is impure?

2. If you touch the root of the hair then will your fingers also get impure and do you have to wash your fingers and make wudhu?

3. If you uproot a hair and you touch it but you feel no stickyness then will your fingers become impure?

4. Sometimes I pull at my sideburns and a hair comes out and it is yellowish in colour at the root but when I touch it there is no stickyness on it. Is the root of that hair impure and did my fingers become impure?

Q: If wet semen or sperm is present on clothes and it dries after a while, would the garment be clean after scraping it off?

Q: What is the ruling on touching ethyl alcohol which is used in labs for making slides? I have a pathology class in which we have to use alcohol. Should I wash my hands after touching alcohol bottles even if they are dry?