What is the average market value in billions of the company with less than 1,705.35 billions in assets, sales of 175.05 billions, and is ranked less than 19?
CREATE TABLE "2007_list" (
  "rank" real,
  "company" text,
  "headquarters" text,
  "industry" text,
  "sales_billion" real,
  "profits_billion" real,
  "assets_billion" real,
  "market_value_billion" real
);
SELECT AVG("market_value_billion") FROM "2007_list" WHERE "assets_billion"<'1,705.35' AND "sales_billion"=175.05 AND "rank"<19;