Table: saloon_car_champ_2
Columns: round
circuit
date
class_a_winner
class_b_winner
class_c_winner
class_d_winner

Question: In which round did Roy Salvadori won Class D and Alan Hutcheson won Class B?
SQL: SELECT "round" FROM saloon_car_champ_2 WHERE "class_d_winner" = 'Roy Salvadori' AND "class_b_winner" = 'Alan Hutcheson'

Question: When did Alan Hutcheson won Class B on round 1?
SQL: SELECT "date" FROM saloon_car_champ_2 WHERE "class_b_winner" = 'Alan Hutcheson' AND "round" = 1