The default duration suffix (and hence duration value) is set on the Schedule tab of the Options dialog box.
	Elapsed time is 24 hours a day, 7 days a week.  For example, a 7 elapsed day (7ed) task "Wait for paint to dry" could start on a Wednesday morning and be complete by the following Tuesday evening.
	If you click on row #11 and then Ctrl+Click on row #6, Project will link from the 1st selected task to the 2nd task selected.  You could also drag and drop a link from the predecessor's bar to the successor's bar.