Yes, you can share the Bluetooth audio from the Era 100 to the Arc. But if the Era 100s are set up as surrounds with the Arc, the Bluetooth functionality is disabled. Read more here:

https://support.sonos.com/en-us/article/share-roam-s-bluetooth-audio-with-your-sonos-system

@GuitarSuperstar , thanks.

I currently have my Arc setup through the HDMIArc to my TV.  So, if I want to have my 2 Era’s setup/connected to the Arc/TV, it won’t work on  bluetooth?
 

Is there a way that I can have the Arc/Era/Era setup connected to both my TV, and my bluetooth turntable easily? (without having to toggle settings in the app to change music sources from TV to turntable, etc?)

When the Era 100s are set up as surrounds in a Sonos home theater setup, it completely disables the Bluetooth and line-in functionality of the Era 100s. So you will NOT be able to connect the turntable to the Era 100s via Bluetooth or line-in without first removing the Era 100s as surrounds from the Arc in the Sonos app. 

Your best option is to get a separate Bluetooth-enabled Sonos device like the Roam or Move 2 and share the Bluetooth audio to your Arc/Era 100s setup. OR, better yet, get a separate Sonos device with line-in like another Era 100, Era 300, Move 2, Five, or Port and connect the turntable to one of these speakers. Then you simply select the Line-In source under Browse in the Sonos app to play the turntable audio to the Arc setup. A line-in connection with the turntable will be much more reliable and sound better than a Bluetooth connection.