user: Question: What is the total number of silver with rank number 6?
Columns: ['Rank', 'Nation', 'Gold', 'Silver', 'Bronze', 'Total']
Types: ['real', 'text', 'real', 'real', 'real', 'real']
Sample row: [1.0, 'Soviet Union', 4.0, 2.0, 0.0, 6.0]
SQL:

assistant: SELECT SUM("Silver") FROM "Table" WHERE "Rank" = 6.0;