Returning to the Mute/Keypad/Speaker Screen While Talking

I will often mute a call and talk to a person in the room, mute so they can't hear my dogs barking, look at email and texts while the person/people are talking etc. I need to unmute the call to talk but now, with ios 8.1, I can't seem to get back to the screen. How do I get back to this screen? Very frustrated at times, frustrated enough to research how to do it and I still can't find it. I know it is probably easy as pie and staring me in the face but I'm just not seeing it.

Also, I often change audio options from speaker, to bluetooth, to iphone while on a call which is on the same options screen and I can't get back to that. I sometimes need to look up contact info while talking so I can share a phone number or address, and that is on that screen as well. Also, the "end" call button was there, and I can't get back to that. Can someone please tell me what apple did with this screen? I looked in the ios 8 user manual (pic below) and there isn't any information.