A $69.0\,\text{g}$ portion of nitrogen dioxide is introduced into a reaction vessel. At first, the pressure of the nitrogen dioxide is $P$. An effective catalyst is then added, and the nitrogen dioxide starts to break down into its elements. After ten minutes, the total pressure has risen to $1.1P$. What is the mass of oxygen molecules in the reaction vessel after ten minutes?
- A$4.80\,\text{g}$
- B$9.60\,\text{g}$
- C$38.4\,\text{g}$
- D$48.0\,\text{g}$