Which of the following numbers are not perfect cubes?
(i) 216                  (ii) 128           (iii) 1000           (iv) 100
(v) 46656

Explanation

To determine which of the given numbers are not perfect cubes, we will find the prime factorization of each number and check if all prime factors can be grouped in sets of three.

### Step-by-Step Solution:

1. **Prime Factorization of 216:**
- Divide 216 by 2:
- \( 216 \div 2 = 108 \)
- Divide 108 by 2:
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