coefficients renormalized at a low scale of order $m_b$. The two sets of coefficients are connected by a renormalization-group transformation [@Heff]. Here we discuss the QCD evolution of the electroweak penguin operators at the leading logarithmic order, neglecting next-to-leading corrections as well as QED corrections to the anomalous dimensions of the operators. Under QCD evolution, flavor-nonsinglet combinations of penguin operators mix into flavor-singlet combinations through diagrams in which two light quarks annihilate into a gluon, which then fragments into a pair of light quarks. However, there is no mixing of flavor-singlet operators into flavor-nonsinglet ones. If we restrict ourselves to flavor-nonsinglet combinations of the operators $O_i^q$, each pair in the three lines in (\[basis\]) obeys a separate matrix evolution equation. It follows that the coefficients $c_i^{\rm EW}$ mix pairwise under renormalization. For each pair of coefficients associated with $(V\mp A)\otimes(V\pm A)$ operators we obtain $$\begin{aligned}
\label{RGE-R}
   c_1^{\rm EW}(\mu) &=& \kappa^{-3/23}\,c_1^{\rm EW}(m_W) \,,
    \nonumber\\
   c_2^{\rm EW}(\mu) &=& \frac{\kappa^{24/23}-\kappa^{-3/23}}{3}\,
    c_1^{\rm EW}(m_W) + \kappa^{24/23}\,c_2^{\rm EW}(m_W) \,,\end{aligned}$$ and similarly for $(c_5^{\rm EW},c_6^{\rm EW})$, where $\kappa=\alpha_s(\mu)/\alpha_s(m_W)$. For a pair of coefficients associated with $(V\mp A)\otimes(V\mp A)$ operators we obtain instead $$\begin{aligned}
\label{RGE-L}
   c_3^{\rm EW}(\mu) &=& \phantom{-}
    \frac{\kappa^{12/23}+\kappa^{-6/23}}{2}\,c_3^{\rm EW}(m_W)
    - \frac{\kappa^{12/23}-\kappa^{-6/23}}{2}\,
    c_4^{\rm EW}(m_W) \,, \nonumber\\
   c_4^{\rm 