adding the poll question

lectures/08_vector_implementation/README.md

@@ -217,11 +217,11 @@ The destructor is called implicitly when an automatically-allocated object goes
 
 Match up the line of code with the function that is called. Each letter is used exactly once.
 
-Foo f1;			a) assignment operator
-Foo\* f2; 		b) destructor
-f2 = new Foo(f1); 	c) copy constructor
-f1 = \*f2;	 	d) default constructor
-delete f2;		e) none of the above
+Foo f1;			a) assignment operator  
+Foo\* f2; 		b) destructor  
+f2 = new Foo(f1); 	c) copy constructor  
+f1 = \*f2;	 	d) default constructor  
+delete f2;		e) none of the above  
 
 ## 8.15 Leetcode Exercises