What percentage of browsers were using Chrome during the period in which 0.30% were using Opera and 6.77% were using Safari?
CREATE TABLE "usa_usage_share_data_from_stat_owl_com" (
  "internet_explorer" text,
  "firefox_other_mozilla" text,
  "chrome" text,
  "safari" text,
  "opera" text
);
SELECT "chrome" FROM "usa_usage_share_data_from_stat_owl_com" WHERE "opera"='0.30%' AND "safari"='6.77%';