user: Question: What was the surface tye during the match with the opponent of Richard Fromberg?
Columns: ['Outcome', 'Date', 'Championship', 'Surface', 'Opponent', 'Score']
Types: ['text', 'real', 'text', 'text', 'text', 'text']
Sample row: ['Winner', 1990.0, 'Florence , Italy', 'Clay', 'Lawson Duncan', '6–7, 7–5, 6–0']
SQL:

assistant: SELECT "Surface" FROM "Table" WHERE "Opponent" = 'Richard Fromberg';