The Directories->Query menu item initiates a query of the selected directory. The query results are shown in a File Info dialog.
If the dialog is already open, selection of any file or directory, using either the mouse or keyboard, will update the data in the dialog.
The File Info dialog show the number of files and subdirectories in the selected directory and the total actual and allocated sizes of the these files and subdirectories.
The allocated size is the actual disk space occupied by these files and subdirectories. The difference between actual and allocated size is the overhead disk space used in storing these files.
Accelerator Keys - Ctrl Q