Question X. (4 points) Write a relational algebra expression for the cars that finished the race in a time smaller than all races average time.

Question XI- (3 points) Write a relational algebra expressions for the racer name that participated in each race.

Instructions When writing a query, write the query in a way that it would work over all possible database instances and not just for the given example instance! Consider the following database schema and example instance for a race car database: Good luck Car Racer A ID Name 1 Sam CID Manufacturer Horse_power Gender Birth_year IM 1984 Nbr of cylinder 6 2 Suzan IF 1982 C1 1200 2400 Alice C2 3 F Mercedes Ferrari Mercedes 1980 8 C3 800 4 Result Race Sponsor R_ID R1 Result_IDC_ID R_ID A_ID Time R1 1 C1 R1 1 400 R1 2 C2 R1 2 600 R1 3 C3 R1 3 375 R_ID Type Location R1 F1 UK R2 RallyCross Portugal R3 F1 USA CID Sponsor C1 Motorola Pepsi C4 Michelin R1 R2 Schema: Racer: (A_ID, Name, Gender, Birth_year) Race (R_ID, Type, Location) Result (Result_ID, C_ID, A_ID, R_ID, Time) C_ID is a foreign key for car and A_ID is foreign key for Racer and R_ID is a foreign key for Race. Sponsor (R_ID, C_ID, Sponsor) Car (C_ID, Make, Horsepower)