Answer:
2, 2, 3, 3
Explanation:
At each level, the two branches multiply to give the number above them. Use your knowledge of multiplication facts to fill in the bubbles.
From the top down, you have ...
36 = 3×12
12 = 2×6
6 = 2×3
The prime factors are the numbers in the circles: 3, 2, 2, 3.
Written in order from smallest to largest, the prime factors of 36 are ...
2, 2, 3, 3