rank npc gold silver bronze total
rank
npc
gold
silver
bronze
total
number
first second
number
number
number
number
number text(text) number number number number
1 china (chn) 95 71 65 231
how many silver medals did poland win ?
WRB JJ JJ NNS VBD-AUX NNP VB .
13
select c4_number from w where c2_first = 'poland'