Is it radius or circumference?
Answer:
3: 
4: 
Step-by-step explanation:
Question 3 can be re-written as:

which equals:

Question 4 can be re-written as:

Doing the first 2 brackets gives us:

Expanding these two:

Simplifying it:

Your answer should be 1/6 because you are dividing thing by the number.
I think the answer is going to be 3s