What is the amount of marginal ordinary income tax rate for single in which the range is $8,351– $33,950?
CREATE TABLE "regular_and_capital_gains_tax_rates_for_" (
  "marginal_ordinary_income_tax_rate" text,
  "single" text,
  "married_filing_jointly_or_qualified_widow_er" text,
  "married_filing_separately" text,
  "head_of_household" text
);
SELECT COUNT("marginal_ordinary_income_tax_rate") FROM "regular_and_capital_gains_tax_rates_for_" WHERE "single"='$8,351– $33,950';