Ammonia gas is passed into water, yielding a solution of density `0.93 g//cm^(3)` and containing `18.6% NH_(3)` by weight. The mass of NH3 per cc of the solution is :
A. 0.17 g / `cm^(3)`
B. 0.34 g / `cm^(3)`
C. 0.51 g / `cm^(3)`
D. 0.68 g / `cm^(3)`
