Benzyl penicillin is absorbed from the human digestive tract by a H+/penicillin symporter that cotransports these 2 species in a 1:1 ratio from the intestinal lumen into the brush border epithelial cells. If the pH of the intestine is 6.2, what pH would have to be established inside the epithelial cells to maintain a penicillin gradient of 40in:1out? Assume a constant delta omega of -0.070V inside.