Set up $3$ VLANs

$192*90*10*\frac{0}{24}$ Engineering

$192*90*20*\frac{0}{24}$ Quality

$192*90*\frac{30\mathrm{.}0}{24}$ Production

Set up $4$ switches

Configure switches as Client$/$Server using VTP

Configure $3$ PCs in each department $($Engineering$,$ Quality, Production$)$ and distribute across all $4$ switches

Add a fourth VLAN $-$ available across all switches $-$ Research & Development

Move $1$ Engineering PC to R&D VLAN

Move $1$ Production PC to R&D VLAN

Add a router to enable interVLAN access

Test connectivity using PING command