For the spring assemblage with arbitrarily numbered nodes shown in Figure, obtain $($a$)$ the global stiffness matrix, $($b$)$

the displacements of nodes $3$ and $4,($c$)$ the reaction forces at nodes $1$ and $2,$ and $($d$)$ the forces in each spring. A force

of $25$ kN is applied at node $4$ in the $x$ direction. The spring constants are given in the figure. Nodes $1$ and $2$ are fixed.