public Form1() { InitializeComponent(); speedMonitorSubject = new SpeedMonitorSubject(); // must create SpeedMonitorSubject first - we need to pass // it in when we call an observer's constructor rpmObserver = new RPMObserver(lblRPM, speedMonitorSubject); caloriesObserver = new CaloriesObserver(lblCaloriesPerHour, speedMonitorSubject); kmsPerHourObserver = new KMsPerHourObserver(lblKMPerHour, speedMonitorSubject); }