\[
\begin{array}{l}
784.14 \mathrm{~g} \div 0.80 \mathrm{~mL} = \boxed{980 \frac{\mathrm{g}}{\mathrm{~mL}}} \\
93.4 \frac{\mathrm{~mol}}{\mathrm{~L}} \times 53 \mathrm{~L} = \boxed{5000 \mathrm{mol}} \\
704.66 \mathrm{~m} \div 64.12 \mathrm{~s} = \boxed{10.99 \frac{\mathrm{m}}{\mathrm{~s}}}
\end{array}
\]