In Each of the Following Situations, Identify the Internal Control

In each of the following situations, identify the internal control weakness as well as the business's potential problem, and suggest a solution.
a. Susan Scandal purchases supplies for Fraud Fortress Company and stores them in a locked room for which she has the key. She is also responsible for distributing these supplies to employees upon request. At the end of each month, Susan takes an inventory of the supplies on hand and notifies the accounting department of the amount for the adjusting entry for supplies used.
b. Jim Devious, an accounting clerk, is responsible for opening the mail, recording and depositing cash receipts, and preparing the monthly bank reconciliation. Jim has not taken a vacation in over five years.
c. The law firm of Dewey, Cheatem & Howe has been extremely busy in recent months. The firm needs another lawyer but has not had the chance to hire one. In the meantime, one of the secretaries has been preparing briefs, writing up wills, and preparing the closing papers for various real estate deals.