Toyota Corp's stock is $$35$ per share. Its expected return is $25\%$ and variance is $11\%.$ Honda Corp's stock is $$21$ per share. Its expected return is $15\%$ and variance is $4\%.$ Benz Corp's stock is $$48$ per share. Its expected return is $12\%$ and variance $5\%.$ The covariance between Toyota and Honda is $0\mathrm{.}03.$ What would be the standard deviation of a portfolio consisting of $50\%$ Toyota and $50\%$ Honda?