Rushton turbine, impeller diameter = 20 cm. Speed = 200 rpm. Flow rate = 0.2 m\(^3\)/min. Find the Froude number $N_{Fr}$ (round to 2 decimals).
Find the sum of eigenvalues of the matrix: \( \begin{bmatrix} 4 & 1 \\ 3 & 6 \end{bmatrix} \)