Suppose that a game has a payoff matrix
A = [\begin{array}{cccc}-20&30&-20&1\\21&-31&11&40\\-40&0&30&-10\end{array}\right]
If players R and C use strategies
p = [\begin{array}{ccc}1/2&0&1/2\end{array}\right] and
q = [\begin{array}{c}1/4\\1/4\\1/4\end{array}\right]
respectively, what is the expected payoff of the game? E(p, q) =