user: Question: Manufac turing b of 16.8, and a 2008 GDP per capita (USD) a smaller than 4162, so what is the total number of mining b?
Columns: ['District', '2010 Population (000)', '2008 GDP (USD bn) a', '2008 GDP per capita (USD) a', 'Agri culture b', 'Mining b', 'Manufac turing b', 'Services & cons truction b', 'Exports (USD mn) 2011', 'Median mo. salary (USD) a e', 'Vehicles (per 1000) d', 'Income poverty f', 'Structural poverty g']
Types: ['text', 'real', 'real', 'real', 'real', 'real', 'real', 'real', 'text', 'real', 'real', 'real', 'real']
Sample row: ['City of Buenos Aires', 2890.0, 118.0, 40828.0, 0.3, 1.0, 12.9, 85.8, '426', 1618.0, 528.0, 7.3, 7.8]
SQL:

assistant: SELECT SUM("Mining b") FROM "Table" WHERE "Manufac turing b" = 16.8 AND "2008 GDP per capita (USD) a" < 4162.0;