Design and implement program that implements the following 3 methods: - Method isValid(...) returns true if the sum of the width and height is greater than 30 boolean isValid (double width, double height){} - Method Area ( ...) returns the area of the rectangle if it is a valid rectangle double Area (double width, double height){} - Method Perimeter(...) returns the perimeter of the rectangle if it is a valid rectangle double Perimeter (double width, double height) { }

HOW TO MODIFYING REGULAR EXPRESSIONS USING ASSERTIONS,WRITE CODE.

What are the stages in building a program function?

Create a case detector program in the C++ language in which the user enters an alphabet and the program should print "Uppercase" if the character is an uppercase alphabet, else print "Lowercase" if the character is a lowercase alphabet. The program should also display an error message if the character entered is not an alphabet.