ms=56g
Vw=69 cm3
dw= 1 g/cm3
dw=mw÷Vw
mw= dw*Vw= 1 g/cm3*69 cm3= 69 g
mr=ms+mw= 56 g+ 69 g= 125 g
Cp=(ms÷mr)*100%
Cp=(56 g÷125 g)*100%= 44,8%
