public void TestAdditionalHours()
{
PriceCalculator calculator = new PriceCalculator();
var dateTime = new DateTime();
var bike = new Bike {
RentalPriceFirstHour = 10, RentalPriceAdditionalHour = 20, Id = 1
};
var rental = new Rental {
BikeId = 1, CustomerId = 1, Id = 1, RentalBegin = dateTime, RentalEnd = dateTime.AddHours(2), Bike = bike
};
var costs = calculator.CalculateCosts(rental);
Assert.AreEqual(30, costs);
}