Let L1 be the line 2x+3y−6=0. A point P(h,2h−3) lies in the plane.
(i) Determine the slope of L1.
(ii) Write the equation of the line L2 that passes through P and is perpendicular to L1.
(iii) If L2 meets the positive x-axis at the point (4,0), find the value of h and hence obtain the explicit equation of L2.