user: Question: When 20 is the rr4 points what is the lowest rr3 points?
Columns: ['Team name', 'Races', 'Won', 'RR1 Pts.', 'RR2 Pts.', 'RR3 Pts.', 'RR4 Pts.', 'Total Pts.', 'Ranking']
Types: ['text', 'real', 'real', 'real', 'real', 'real', 'text', 'real', 'real']
Sample row: ['Team New Zealand', 24.0, 23.0, 6.0, 10.0, 24.0, '30', 70.0, 1.0]
SQL:

assistant: SELECT MIN("RR3 Pts.") FROM "Table" WHERE "RR4 Pts." = '20';