Consider a single-step market model with three risky securities with returns K1,K2,K3. Suppose that the expected returns, standard deviations and correlations are as follows: Expected returns: 1=0.152=0.103=0.10 Standard deviations: 1=0.202=0.153=0.10 Correlations: 12=0.3023=0.1031=0.20 (i) Compute the covariance matrix, determine whether it is invertible and compute its inverse