The rate equation for the reaction \(2 A+B \longrightarrow\) products is rate \(=k[A][B]^2\).
If \(k\) at \(T(\mathrm{~K})\) is \(5.0 \times 10^{-6} \mathrm{~mol}^{-2} \mathrm{~L}^2 \mathrm{~s}^{-1}\), the initial rate of the reaction, when \([A]=0.05 \mathrm{~mol} \mathrm{~L}^{-1}\) and \([B]=0.1 \mathrm{~mol} \mathrm{~L}^{-1}\) is

1. A \(1.25 \times 10^{-9} \mathrm{~L} \mathrm{~mol} \mathrm{~L}^{-1} \mathrm{~s}^{-1}\)
2. B \(1.25 \times 10^{-9} \mathrm{~mol} \mathrm{~L}^{-1} \mathrm{~s}^{-1}\)
3. C \(2.50 \times 10^{-9} \mathrm{~mol} \mathrm{~L}^{-1} \mathrm{~s}^{-1}\)
4. D \(2.50 \times 10^{-9} \mathrm{~L} \mathrm{~mol} \mathrm{~L}^{-1} \mathrm{~s}^{-1}\)