Employ stiffness matrix approach for the simply supported beam as shown in the figure to calculate unknown displacements/rotations. Take length, \( L = 8 \, \text{m} \); modulus of elasticity, \( E = 3 \times 10^4 \, \text{N/mm}^2 \); moment of inertia, \( I = 225 \times 10^6 \, \text{mm}^4 \).
The mid-span deflection of the beam (in mm, round off to integer) under P = 100 kN in downward direction will be \(\underline{\hspace{1cm}}\)
