For each action listed below, identify the internal control principle followed.

Separate recordkeeping from custody of assets.

Insure assets and bond key employees.

Maintain adequate records.

Apply technological controls.

Perform regular and independent reviews.

Employees who open the mail are not allowed to record customer payments in the accounting system.

External auditors are regularly hired to evaluate internal controls.

Insurance policies are purchased for buildings and vehicles, and to protect against losses from theft by an employee.

Digital time clocks are used to register which employees are at work at what times.

Detailed records are kept of suppliers and accounts payable