Answer:
Miguel should send a e-mail informing the entire staff about new dress code.
Step-by-step explanation:
The excerpt indicates that all the people in the staff has a networked computer and this means that all the devices are connected to each other and are able to share data and have access to the internet. This allows Miguel to send an e-mail to everyone which is a quick way to inform them about the dress code as they will all receive the same information at the same time.