Write the definition of a class telephone. the class has no constructors, one instance variable of type string called number, and two static variables. one is of type int called quantity; the other is of type double called total. besides that, the class has one static method makefullnumber. the method accepts two arguments, a string containing a telephone number and an int containing an area code. the method concatenates the two arguments in the following manner: first comes the area code, then a dash, then the telephone number. the method returns the resultant string.