© npr.org هنا water molecules multiple stars seven quintillion, five hundred quadrillion grains of sand more H2O molecules in just 10 drops of water NPR article NPR universal this NPR article study it's roughly estimated the number of grains of sand on earth Source © npr.org NPR © npr.org هنا Scientists estimate researchers at the University of Hawaii 75,000,000,000,000,000,000 grains of sand on earth grains of sand are in the world هنا www.npr.org...