Find the value of kkk if the matrix determinant det(0.5k0.20.4)=0.04\det \begin{pmatrix} 0.5 & k \\ 0.2 & 0.4 \end{pmatrix} = 0.04det(0.50.2k0.4)=0.04.
0.20.20.2
0.40.40.4
0.60.60.6
0.80.80.8