How much pee is in this pool?
Number Sense Geometry Math and Science Funny Wow factor
After chlorination, it has been hard to measure the quantity of pollutants in pool water.  A Canadian chemist, Xing-Fang Li, has found a marker for urine that chlorine doesn't disguise....
Data and Probability 5.MD 6th 7th 5th 4th 4.MD.C 7.G.B 6.G.A 6.RP.A 7.RP.A unit ratio G.G.C ratios of volume Volume pee