Verifies and enters details of costs, charges or other similar bookkeeping items to correct accounts or classifications; Receives, receipts and deposits cash collections of various kind, and maintains appropriate records; consults or studies specific books, manuals, catalogs or other sources in order to obtain desired information; Performs numerous types of computations such as discount, interest, ratio and percentage; determines rates, costs, amounts or other specifications for various types of items, selecting and using tables or classification data; Explains details of services, methods or policies; prepares requisitions or purchase orders, and may place orders for supplies, materials, equipment or contract services; processes invoices and may prepare vouchers for approval to authorize disbursement; May maintain inventory control records; Reviews the accounts clerical work of others, calling attention to use of incorrect procedures or methods and to incorrect entries or results; Composes correspondence requiring specific knowledge of methods, procedures, policies or other information; determines the general ledger accounts, journals and subsidiary accounts affected and the debit and/or credit entries to be made; summarizes transactions having a like effect and preparing control sheets or other posting documents reflecting the debit and/or credit entries to be made; Totals entries at specified intervals and takes a trial balance of debits and credits; determines corrective entries required to bring accounts into balance; closes and reconciles accounts; May supervise one or more lower-level account clerk or other subordinates. Supervisory aptitude is the demonstration of aptitude or potential for the performance of supervisory duties through successful completion of regular or special assignments which involve some supervisory responsibilities or aspects; by serving as a group or team leader, or in similar work in which opportunities for demonstrating supervisory capabilities exist; by completion of training courses in supervision accompanied by application of supervisory skills in work assignments or by favorable appraisals by a supervisor indicating the possession of supervisory potential.