Which of the following sentences are statements ? Give reasons for your answer.
(i) there are 35 days in a month.
(ii) mathematics is difficult.
(iii) the sum of 5 and 7 is greater than 10.
(iv) the square of a number is an even number.
(v) the sides of a quadrilateral have equal length.
(vi) answer this question.
(vii) the product of (-1) and 8 is 8.
(viii) the sum of all interior angles of a triagle is `180^@`.
(ix) today is a windy day.
(x) all real numbers are complex numbers.

Explanation

To determine which of the given sentences are statements, we need to understand what a statement is. A statement is a declarative sentence that can be classified as either true or false, but not both simultaneously. Let's analyze each sentence one by one.

### Step-by-Step Solution:

1. **Sentence (i): "There are 35 days in a month."**
- **Analysis:** This statement is false because no month has 35 days.
- **Conclusion:** This is a statement (False).

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