Express the following numbers to four significant figures :
(i) 5.607892 (ii) 32.392800 (iii) `1.78986 xx 10^3` (iv) 0.007837.

Explanation

To express the given numbers to four significant figures, we will follow the rules of significant figures and rounding. Here’s the step-by-step solution for each number:

### (i) 5.607892
1. Identify the first four significant figures: 5, 6, 0, and 7.
2. The next digit after 7 is 8, which is greater than 5. Therefore, we round up.
3. Rounding 7 up gives us 8.
4. The final result is **5.608**.

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