Question 141. Which of the following is/are true for an abstract class?
1. A class is declared abstract by prefacing the definition with the word abstract.
2. A class is declare abstract by using the keyword implements.
3. It is a class that really isn’t supposed to ever be instantiated but instead serves as a base class.
4. Attempting to instantiate an abstract class results in an error.

Question 142. If one intends to create a model that will be assumed by a number of closely related objects, which class must be used?

Question 143. If your object must inherit behavior from a number of sources you must use a/an

Question 144. Which method is used to tweak an object’s cloning behavior?

Question 145. Which feature allows us to call more than one method or function of the class in single instruction?

Question 146. You can overwrite a Singleton with the wrong kind of data. 

Question 147. PHP have not yet supported constructor overloading.