Find the sum of indicated terms of each of the following geometric progressions :
(i) 2, 4, 8, 16 ,…, 20 terms
(ii) ` 1 , (-2)/(3) , (4)/(9) , (-8)/(27) ,…, 10 ` terms

Explanation

To solve the problem of finding the sum of indicated terms of the given geometric progressions, we will break it down into two parts.

### Part (i): Sum of the first 20 terms of the geometric progression 2, 4, 8, 16, ...

1. **Identify the first term (a) and common ratio (r)**:
- The first term \( a = 2 \)
- The common ratio \( r = \frac{4}{2} = 2 \)

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