A Formula One fan club wants to set up a database to keep track of the results of all the seasons since the first Formula One World championship in 1950. A season is held on a year, between a starting date and an ending date, has a number of races, and is described by a summary and a set of regulations. A race has a round number (stating the ordering of the race in a season), an official name (e.g., 2013 Formula One Shell Belgian Grand Prix), a race date, a race time (expressed in both local and UTC time), a description of the weather when the race took place, the pole position (consisting of driver name and time realized), and the fastest lap (consisting of driver name, time, and lap number). Each race of a season belongs to a Grand Prix (e.g., Belgian Grand Prix), for which the following information is kept: active years (e.g., 19501956, 1958, etc. for the Belgian Grand Prix), total number of races (58 races as of 2013 for the Belgian Grand Prix), and a short historical description. The race of a season is held on a circuit, described by its name (e.g., Circuit de Spa-Francorchamps), location (e.g., Spa, Belgium), type (such as race, road, street), number of laps, circuit length, race distance (the latter two expressed in kilometers), and lap record (consisting of time, driver, and year). Notice that over the years, the course of the circuits may be modified several times. For example, the Spa-Francorchamps circuit was shortened from 14 to 7 km in 1979. Further, a Grand Prix may use several circuits over the years. For example, the Belgian Grand Prix has been held alternatively in the SpaFrancorchamps, Zolder, and Nivelles circuits. A team has a name (e.g., Scuderia Ferrari), one or two bases (e.g., Maranello, Italy), and one or two current principals (e.g., Stefano Domenicali). In addition, a team keeps track of its debut (the first Grand Prix entered), the number of races competed, the number of world championships won by constructor and by driver, the highest race finish (consisting of place and number of times), the number of race victories, the number of pole positions, and the number of fastest laps. A team competing in a season has a full name, which typically includes its current sponsor (e.g., Scuderia Ferrari Marlboro from 1997 to 2011), a chassis (e.g., F138), an engine (e.g., Ferrari 056), and a tire brand (e.g., Bridgestone). For each driver, the following information is kept: name, nationality, birth date and birth place, number of races entered, number championships won, number of wins, number of podiums, total points in the career, number of pole positions, number of fastest laps, highest race finish (consisting of place and number of times), and highest grid position (consisting of place and number of times). Drivers are hired by teams competing in a season as either main drivers or test drivers. Each team has two main drivers and usually two test drivers, but the number of test drivers may vary from none to six. In addition, although a main driver is usually associated with a team for the whole season, it may only participate in some of the races of the season. A team participating in a season is assigned two consecutive numbers for its main drivers, where the number 1 is assigned to the team that won the constructors world title the previous season. Further, the number 13 is usually not given to a car, it only appeared once in the Mexican Grand Prix in 1963. A driver participating in a Grand Prix must participate in a qualifying session, which determines the starting order for the race. The results kept for a driver participating in the qualifying session are the position and the time realized for the three parts (called Q1, Q2, and Q3). Finally, the results kept for a driver participating in a race are the following: position (may be optional), number of laps, time, the reason why the driver retired or was disqualified (both may be optional), and the number of points (scored only for the top eight finishers). (a) Design an ER schema for this application. In particular, state the identifiers and the derived attributes. Note any unspecified requirements and integrity constraints, and make appropriate assumptions to make the specification complete. If you need additional information, you may look at the various existing Formula One web sites. (b) Translate the ER schema above into the relational model. Indicate the keys of the relations, and the referential integrity constraints, and the non-null constraints.