'Luxuryforyou' has car experts called Sales Agent1 that interact with individuals (called Sellers) who would like to sell their cars to 'Luxuryforyou'. A seller can sell many cars while Sales Agent1 can be involved with multiple sellers. The make, model, miles, color, and any additional feature of a particular car that a seller is trying to sell needs to recorded. The SalesAgent1 must record their own name, phone number, date they first interacted with a potential seller. Also, the 'sale price' of the car, which is a mutually agreed price between the seller and SalesAgent1 must be recorded, along with the date/time of sale. Before finalizing the sale (that is before 'Luxuryforyou' approves the purchase of a car from a seller), the 'QualityCheck' division at 'Luxuryforyou' runs a background check on a car (for title, accident records etc). The 'Quality Check' department can check multiple cars (that sellers are trying to sell), while it only does background check once for a car that a seller is trying to sell. How many are entities should be ? What are their relationships?