Exercises 479 6. 7. Created a label and buttons and positioned them inside the View window. Control-click-dragged from the label you created in the View window to the UILabel IBOutlet property display . Control-click-dragged from each button in the View window to the appropriate IBAction method. For each digit button, you selected the clickDigit: method. Also, for each digit button, you set the tag property to the corresponding digit 0-9 so that the clickDigit: method could identify which button was pressed. 8. It was a worthwhile exercise learning how to use a view controller, even though it was more work than simply doing everything in the application delegate object. Hopefully this brief introduction to developing iOS applications gives you a good start for writing your own iPhone applications.As noted earlier, there are many features offered in UIKit and lots for you to explore! There are several limitations with our fraction calculator application. Many of these are addressed in the exercises that follow. Exercises 1. Add a Convert button to the fraction calculator application.When the button is pressed, use the Fraction class's convertToNum method to produce the numeric