Suppose you have written JavaScript constructors for two obj…

Suppose you have written JavaScript constructors for two object classes called ClassA and ClassB and then the statement ClassA.prototype = new ClassB();. ClassB can use the value returned by one of ClassA’s methods in one of its own methods because ClassB inherits all the properties and methods of ClassA in this situation.

Imagine that you are working on a web form. After writing th…

Imagine that you are working on a web form. After writing the JavaScript statementlet pinNo = document.getElementById(“pinNo”);what statement can you add to assign a Boolean value of true to isValid if the value in the pinNo field is matched by the regular expression /^\d{4}$/ or assign a value of false to isValid if it isn’t?