$4\mathrm{.}2.$ For each case, plot the force exerted on the mass by the springs as a function of the displacement $\backslash ($ x $\backslash )($Figure P$4\mathrm{.}2).$ Neglect friction.

$($a$)$

$($b$)$

$($c$)$

Figure P$4\mathrm{.}2$