Hi 

I have included a photo concerning my question. 
The respective chords are shown in boxes adding up to 12.
Each box represents on bar of four beats is this correct?

Are these chords played as dominant seventh chords A7 D7 and E7 

chords each for four downstrums. Does the above diagram illustrate these seventh chords.

How can I use guitar tricks jam tracks tool to practice this to

what speed should I set my metronome to