Who was supporting in round 1 where the gt winning car was dodge viper?
CREATE TABLE "table1_28490105_1" (
  "rnd" real,
  "date" text,
  "circuit" text,
  "supporting" text,
  "distance" text,
  "gt_winning_car" text,
  "tc_winning_car" text
);
SELECT "supporting" FROM "table1_28490105_1" WHERE "gt_winning_car"='Dodge Viper' AND "rnd"=1;