A ribosome has two subunits, and each subunit includes rRNA. When all the $70\text{S}$ ribosomes in one Escherichia coli cell were examined, the results showed $38\,000$ rRNA molecules, $2$ principal kinds of rRNA molecule, and $19\,000$ copies of each rRNA type. What number of $70\text{S}$ ribosomes were present in the E. coli cell?
- A9500
- B19600
- C38600
- D76600