Douglas company has the following,

1 a pre-numbered shipping document is used for each shipment to customers.

2. The employee who writes checks cannot make entries in the general ledger.

3. An internal auditor reconciles the bank statement each month.

4. The company stores inventory in a room that is monitored by cameras

5. The manger is required to authorize purchases before they are made by employees,

For each item, identify the internal control principle that is being followed.