So in example three, we want to basically determine the net charge on this protein that consists of five amino acids at these four different pieces h value. So let's begin by actually drawing the structure of this protein. So let's begin with histidine. So we have our actually, we're not going to have enough room, so let's draw it lower. We have h three M, and we have our essential carbon atom. The h is going into the board and we have our group.