Table: olympic_coins
Columns: year
denomination
alloy
reverse
diameter
weight
obverse
mintage
series

Question: what's the series with reverse being swimming
SQL: SELECT "series" FROM olympic_coins WHERE "reverse" = 'Swimming'

Question: what's the alloy with series being ii series
SQL: SELECT "alloy" FROM olympic_coins WHERE "series" = 'II series'

Question: what's the denomination with year being 2008 and reverse being football
SQL: SELECT "denomination" FROM olympic_coins WHERE "year" = 2008 AND "reverse" = 'Football'

Question:  how many reverse with series being iii series
SQL: SELECT COUNT("reverse") FROM olympic_coins WHERE "series" = 'III series'