the oxygen o and the carbo dioxide, the only place they get across is at the great like structures. jerry: you mentioned several reasons for mr. floyd's low oxygen and i want to capture those for the jury then we will talk about them. you mentioned one, handcuffs into the street -- handcuffs and the street, right? dr. tobin: correct. jerry: you mentioned knee on the neck. dr. tobin: correct. jerry: sorry for my writing -- you will know what i did not get an a on in school. the prone position and then that knee on the -- the knee on the back, farm and side -- back, arm and side. we went to talk about each of these, but before we do that what it beheld all for explaining the testimony to the jury for them to see the relative positioning of the various officers on mr. floyd's body while he was subdued on the ground? dr. tobin: yes. jerry: did you assist in making an illustration? dr. tobin: i did. jerry: let me show you what has been marked as exhibit 949. can you tell us, described generally for the record what it is. dr. tobin: i watched the videos and certain segments of the videos