Logic Pro X - Mute a Region - how?

I want to mute a region in Logic Pro X. However, I am unable to follow these instructions (link below) because I do not know where the "mute tool" is located. I am aware of, and have used, the mute button - but, it is my understanding that the mute button mutes the entire track. I only wish to mute a region of a track - not the entire track.

https://support.apple.com/kb/PH13041?locale=en_US

EDIT: I am working with audio tracks - I want to mute an audio track from measure 72 onward.