Question: What are the additional major sponsors which correspond to the additional color Black and a year 1984?
SQL: SELECT "Additional major sponsor(s)" FROM "2-11262643-5" WHERE "Additional colour(s)" = 'Black' AND "Year" = 1984.0;

Question: What is the average year of entries with additional color Black?
SQL: SELECT AVG("Year") FROM "2-11262643-5" WHERE "Additional colour(s)" = 'Black';