REFER TO ROADWAY DRAWINGS FOR PROPOSED GUARDRAIL LOCATIONS AND 3.0m PAVED SHOULDER -1,80m BLACK VINYL CHAIN-UNK FENCE PER OPSD 972.130 POST SUPPORT WITH SLEEVE-IT 1224R SYSTEM BY NILEY OR APPROVED ALTERNATE FILLED WITH CONCRETE HIGH - 500 (MIN) GRADE EL 1.0 m 2.5(MN)\\SWALE 481 EXISTING GROUND 200 CLAY CAP-/ EXISTING GROUND 4.0 m 1.5 m 25M @ 303) 35M @ 300 15M 8 300- 25N @ 150 354 0 150 150x160 KEY L 15M @ 300- -900- 15m @ 300- 25m @ 1500- -1500- -SHEAR KEY 1200 J. 750 4050 BOO0 SECTION SCALE 1:50The preliminary design drawing (cross section) for the retaining wall of project XYZ is shown below (PDF file is attached). The length of the retaining wall = 20.0 n1. The retaining wall should be constructed in 4 steps. Each step will have 5-meter in length. It is required to: 1. Develop work breakdown structure for the retaining wall (30%). 2. Develop bar chart and activity network for the retaining wall (30%). 3. Determine project duration. Use your engineering knowledge to determine the construction duration for each activity (40%)