SELECT "State Rank by Revenue" FROM table_24675 WHERE "Revenue ($billions) 2012 estimate" = '6.8'
What is the state rank of the company with 6.8 billion in revenue?
CREATE TABLE table_24675 (
    "State Rank by Revenue" real,
    "Company Name" text,
    "National Rank" real,
    "Revenue ($billions) 2012 estimate" text,
    "Headquarters City" text,
    "Known for" text
)