You are concerned about the adequacy of the substantive audit work done by Garcia and Foster. You decide to carefully and in detail review the account receivable aging substantive testing (AR.4.1-AR.4.5), account receivable confirmation testing (AR.5.1-AR.5.8), sales cutoff testing (AR.6.1-AR.6.7), and the testing of the allowance for doubtful accounts (AR.7.1). This question relates to Step 4 of the Garcia and Foster Audit Plan. Identify any of the following issues: a. Did they perform all of the steps associated with the audit program? b. Did they perform the steps accurately? If not, then specifically state the nature of the problem and follow up on it to the extent possible with the information given. c. Do you see any other issues or problems with the auditors' work or client documentation?