Code C, Excavation, Dig and Grade is not 100 hours in this case, it is 80 hours, thus, please answer as if Code C is 80 hours.

3.8 The City of Lethbridge has decided to build a botani- cal garden and picnic area in the heart of the city for the recreation of its citizens. The precedence table for all the activities required to construct this area successfully is given below. Draw the Gantt chart for the whole construction activity. Time (in hours) Code A 20 B 60 C 100 D 30 Activity Planning Purchasing Excavation Sawing Placement Assembly Infill Outfill Decoration Description Find location, determine resource requirements Requisition of lumber and sand Dig and grade Saw lumber into appropriate sizes Position lumber in correct locations Nail lumber together Put sand in and under the equipment Put dirt around the equipment Put grass all over the garden, landscape, paint Immediate Predecessor(s) None Planning Planning Purchasing Sawing, excavation Placement Assembly Assembly Infill, outfill E 20 F 10 G 20 H 10 I 30