CREATE TABLE "classification" (
  "driver" text,
  "constructor" text,
  "laps" real,
  "time_retired" text,
  "grid" real
);

Question: what is the grid when the time/retired is oil pressure and the laps are more than 50?
SQL: SELECT AVG("grid") FROM "classification" WHERE "time_retired"='oil pressure' AND "laps">50;

Question: what is the grid when the time/retired is 1:46:42.3?
SQL: SELECT SUM("grid") FROM "classification" WHERE "time_retired"='1:46:42.3';