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

• A
  $1.25 \times 10^{-9} \, mol \, L^{-1} \, s^{-1}$
• B
  $5.00 \times 10^{-9} \, mol \, L^{-1} \, s^{-1}$
• C
  $2.50 \times 10^{-9} \, mol \, L^{-1} \, s^{-1}$
• D
  $1.00 \times 10^{-8} \, mol \, L^{-1} \, s^{-1}$