the code of accounts is used to provide a hierarchical structure for the deliverables identified in the WBS. 1 is incorrect because the chart of accounts is an accounting tool for assigning pre-defined costs for deliverables such as cost per square foot, cost per hour, or cost per unit. 2 is incorrect; a bill of materials identifies all of the materials needed to create the things identified in the WBS. 4 is incorrect because the WBS dictionary defines what each work package in the WBS is and its associated time and cost estimate.