Which of the following expressions are equivalent?
Only expressions 1 and 2 are equivalent.
 B. 
Only expressions 1 and 3 are equivalent.
 C. 
Only expressions 2 and 3 are equivalent.
 D. 
Expressions 1, 2, and 3 are equivalent.
                                             
                                          
                                          
                                        
											 
					                  