Link two symbols to show a date range

Question:  

If I want to link two symbols with a line to show a date range in dates, how do I do that?  For example:

Answer:

 Add a horizontal bar between two existing symbols on your schedule:

1. 1. Click  the plus tool in the toolbox

   2. In the schedule area, click once on the first symbol.

   3. In the toolbox, click once on a horizontal bar, even if that bar is already highlighted.

   4. In the schedule area, click once on the second symbol.