Please consider the following requirements for the Somerset Levels network.

It should have static routes running on all segments

The mask for the VLAN $10$ and VLAN $20$ segments is $255\mathrm{.}255\mathrm{.}255\mathrm{.}224,$ where every other subnet mask should be $255\mathrm{.}255\mathrm{.}255\mathrm{.}0.$

All devices in all local networks should be able to ping and browse everywhere.