To try out for national team, the athletes have to qualify elite in a sanctioned meet prior to national team trials...I can't
remember off the top of my head what the qualifying difficulty score is to qualify elite, but I think it's a combined 8.0 or 8.3.... After the athlete quality elite, they can compete lower difficulty. There are several athletes on the USTA national team that compete advanced, but not elite. Some of them only compete elite, and some compete advanced and elite...
Sample 5 skill:
Barani, full, whip, whip, double full, punch front...
Sample 8 skill:
Roundoff, whip, whip, full, whip, flic, full, punch front
Or, you could do a 5 skill of:
Roundoff whip, flic, flic, double back
There are tons of variations in skill combos for passes at that level...