1. If you are happy with the narration, click the Save button in the lower right of the dialog box and then click the Close button.
If you are not happy with the audio and wish to rerecord, on the Add/Replace tab, click the Record button again and rerecord the audio. When finished, click the Save button and then click the Close button.
2. On the Filmstrip, notice that the thumbnail for slide 2 contains a tiny speaker icon, an indication that audio has been added to the slide.