Answer
Delete is completed by selecting "Select" the image you want to delete and clicking the "delete button".... In this process, image deletion is completed when you click the "Delete" button...
Please note that data can not be restored, such as when deleted accidentally...
** Notes on image deletion**
* "In use" massage is displayed in the list when the image being used in one of the parts..
* There is no restriction on deletion of the image "in use".. As well if you accidentally delete the image "in use", the image of the public page will not be displayed..
* Please note that the image data can not be recovered after the deletion processing is completed...