Describe what a layer 3 router is and what are its advantages and drawbacks compared to other network devices.

Did you mean layer 3 switch? Because a router always operates at layer 3

Explanation:

If the answer is yes, then a layer 3 is a switch that combines the functions of a switch and a router. So it is capable of operate layer 2 and layer 3. Some of its benefits are: Support routing between VLAN, decrease network latency because the packets don’t have to make extra hops to go through a router and reduce security management. But they are really expensive and lack of WAN functionality so they are used mostly for large intranet environments.

depends on what software you are using. google docs or microsoft word or other?