on page 529 of the text (right before section 18.3) the energy available from the proton gradient was derived. this assumes that the ph is 1.4 units lower in the im space than in the matrix and that the potential inside the matrix is 0v and in the im space is 0.14v. how much energy would be available if instead the ph in the im space was 3.5 units lower instead of 1.4? assume t