A crown is made of an alloy of gold and silver The crown weighs 1000 g in air and 940 g in water. What percentage of gold was it? Density of gold and silver are respectively 19.3 g/cm³ and 10.5 g/cm³?
a. 53.1%
b. 67.4%
c. 81.2%
d. 91.3%