Q$4).$ A three hinged parabolic arch ACB is hinged at the supports A and $B$ which are below the crown hinge $C$ by $4\mathrm{.}9m$ and $8\mathrm{.}1m$ respectively. The span of the arch is $30m.$ The arch carries a uniformly distributed load of $20k\frac{N}{m}$ from A to C$.$ Find the horizontal thrus$/$and bending moment, radial shear normal thrust at a section $7m$ from the support $A.$