I am planing to finish my basement bathroom in a single house built 2 years ago in Maryland. I have some question about these pipe rough ins. The are 2 biger ones. one is black 5" and in 2 ft away is a 4 " white one. I guess the black one is for toilet. but what is the white one for? if for the shower drain, it is too close to the toilet and is just 2 food in front of the sink drain pipe. There are another two 2"pipes behighd the 2 bigger ones.. one with tee connection and connect to the first floor for vent, I guess this is for sink drain, and another one without Tee connection, I guess this is for tube drain. Also, How do I know there is or is not a P trap under the cement fo r the tube? Do I need connect any more vent for the tube or toilet?