CREATE TABLE "usage_share_data_from_wikimedia_visitor_" (
  "period" text,
  "internet_explorer" text,
  "firefox" text,
  "chrome" text,
  "safari" text,
  "opera" text,
  "other_mozilla" text,
  "mobile" text
);

Question: What percentage of users were using mobile browsers during the period in which 2.62% were using Opera?
SQL: SELECT "mobile" FROM "usage_share_data_from_wikimedia_visitor_" WHERE "opera"='2.62%';

Question: What percentage of users were using mobile browsers during the period in which 9.00% were using Chrome?
SQL: SELECT "mobile" FROM "usage_share_data_from_wikimedia_visitor_" WHERE "chrome"='9.00%';

Question: What percentage of users were using Safari during the period in which 30.82% were using Firefox?
SQL: SELECT "safari" FROM "usage_share_data_from_wikimedia_visitor_" WHERE "firefox"='30.82%';

Question: What percentage of users were using Internet Explorer during the period in which 2.1% were using mobile browsers?
SQL: SELECT "internet_explorer" FROM "usage_share_data_from_wikimedia_visitor_" WHERE "mobile"='2.1%';

Question: What percentage of users were using other Mozilla browsers during the period in which 9.00% were using Chrome?
SQL: SELECT "other_mozilla" FROM "usage_share_data_from_wikimedia_visitor_" WHERE "chrome"='9.00%';