Write the following sets in the set-builder form :
(i) `{3,6,9,12}`
(ii) `{2,4,8,16,32}`
(iii) `{5,25,125,625}`
(iv) `{2,4,6,.....}`
(v) `{1,4,9,......100}`.

Explanation

To express the given sets in set-builder form, we will identify a general rule or pattern that generates the elements of each set. Let's go through each set step by step.

### Solution:

**(i) Set: `{3, 6, 9, 12}`**

1. **Identify the pattern**: The numbers are multiples of 3.
2. **General form**: We can express this as \( x = 3n \), where \( n \) is a natural number.
...