Table:
text: List of tennis stadiums by capacity
Davis Cup and Federation Cup venues
Davis Cup and Federation Cup venues
Rank_ Stadium Capacity City Country
1 Queensland Sport and Athletics Centre 49000 Brisbane Australia
2 Estadio Olímpico de Sevilla 27200 Seville Spain
3 Belgrade Arena 23000 Belgrade Serbia
4 Las Ventas 21000 Madrid Spain
5 Royal Dublin Society 6000 Dublin Ireland
6 O2 Arena (Prague) 17000 Prague Czech Republic
7 Palau Sant Jordi 16500 Barcelona Spain
8 Estadio Mary Terán de Weiss 14510 Buenos Aires Argentina
9 Palacio de Deportes de Santander 14000 Santander Spain
10 Memorial Coliseum 12000 Portland, Oregon United States
11 Nokia Arena 11700 Tel Aviv Israel
12 Public Auditorium 11500 Cleveland United States
13 Mediolanum Forum 11200 Milan Italy

text: List of tennis stadiums by capacity
Davis Cup and Federation Cup venues
Davis Cup and Federation Cup venues
Rank_ Stadium Capacity City Country
14 Bill Graham Civic Auditorium 7000 San Francisco United States
15 Sibamac Arena 4500 Bratislava Slovakia
16 Idrottens Hus 2400 Helsingborg Sweden

Question: Which rank has a capacity less than 12,000 and a United States country among the list of tennis stadiums by capacity Davis Cup and Federation Cup venues?

Question: Which capacity is the lowest ranking below 15 and city of Belgrade among Davis Cup and Federation Cup venues in the list of tennis stadiums by capacity?