using System.Data.SqlClient; public class CarDal : ICarDal { private string connectionString = "In this example, the `Get()` method retrieves a car object from the database based on its ID. It uses the `SqlConnection` class to connect to the database and the `SqlCommand` class to execute a SQL query. The method returns a car object if it exists in the database, otherwise it returns `null`. The package library used in this example is likely the SQL Server package (`System.Data.SqlClient`) which provides classes for connecting to and interacting with SQL Server databases."; public Car Get(int carId) { Car car = null; using (SqlConnection connection = new SqlConnection(connectionString)) { SqlCommand command = new SqlCommand("SELECT * FROM Cars WHERE CarId = @CarId", connection); command.Parameters.AddWithValue("@CarId", carId); connection.Open(); SqlDataReader reader = command.ExecuteReader(); if (reader.Read()) { car = new Car { CarId = (int)reader["CarId"], Make = reader["Make"].ToString(), Model = reader["Model"].ToString(), Year = (int)reader["Year"], RentalPrice = (decimal)reader["RentalPrice"] }; } reader.Close(); } return car; } }