How to dissolve an activity in Primavera P6

Primavera P6 has a built-in operation called Dissolve Activity that allows us to delete an activity without deleting its Relationships;. As you see in the above image, After Dissolving Activity2, Predecessor of Activity 2 becomes predecessor for Activity3. 

As shown in the below image, I have a project with three activities. The A1 successor is A2 & the A2 successor is A3. The relationship type is Finish-to-Start

I have dissolving the Activity A2 by Right click on it and select Dissolve ; Activity A2 will get deleted.

After schedule the project again. A1 linked to A3 automatically.