1 Pour 1 cup (120g) of borax and 1/4 cup (60ml) of lemon juice into the toilet bowl. 2  Let sit overnight. 3  In the morning, scrub with a toilet brush, then flush to rinse. 4  Easy! 5  For tough stains, make a borax and lemon juice paste. 6  Scoop some of the water out of the toilet to expose the stain, then rub the paste into it.
Purchasing power parity (PPP) is a theory which states that exchange rates between currencies are in equilibrium when their purchasing power is the same in each of the two countries.
Net Primary Productivity (NPP) is the amount of carbon uptake after subtracting Plant Respiration (RES) from Gross Primary Productivity (GPP). GPP is the total rate at which the ecosystem capture and store carbon as plant biomass, for a given length of time. NPP = GPP â RES.