A triangular park △LMN is being redesigned. Benches are to be placed along the mid-points of each side so that people can walk around a central paved region formed by joining a vertex to these three mid-points. Points D, E and F are the mid-points of LM, LN and MN respectively.
(i) Explain why the paved region enclosed by L, D, F and E is a parallelogram.
(ii) Prove that the area of the paved region is half the area of the entire park △LMN.
(iii) The park has base MN=60 m and corresponding altitude h=48 m. Find the area of the paved region.