Table schema:
CREATE TABLE table_name_39 (investment_income VARCHAR, other_social_security_benefits VARCHAR, occupational_pensions VARCHAR, working_tax_credit VARCHAR)

Question: Occupational pensions of 7%, and a Working tax credit of 2%, and a Other social security benefits of 6% has what investment income?
SQL: SELECT investment_income FROM table_name_39 WHERE occupational_pensions = "7%" AND working_tax_credit = "2%" AND other_social_security_benefits = "6%"