Observe the pattern below.
YCIND_250706_7389_expressions_36.png   YCIND_250706_7389_expressions_37.png   YCIND_250706_7389_expressions_38.png
 
1. How many squares will be there in step 4, step 33, step 69?
 
Step 4:
 
Step 33:
 
Step 69:
 
2. Write a general formula:
 
3. How would the formula change if we want to count the number of vertices of all the squares?