What unit is primarily used for coal

According to bowlby which of the following is not required in order for infants to form healthy attachments with their parents

The patient had a wire localization performed by radiology and was taken to the operating room. under local anesthesia of the left breast was prepped and draped in a sterile manner. a breast line incision was made through the entry point of the wire, and a core of tissue surrounding the wire approximately 1x2cm was removed

If human development really does proceed continuously, what value does stage theories of development have?