And we have to also label their PKA value. So let's begin on this side. So this right over here has a PKA value of 8.0. So let's underline that this group here, or let's actually go to this group, this group here, which is our histidine. So this nitrogen, right, can gain or lose an h atom at a PKA of 6.0. Okay, now let's go to tyrosine.