List of top Mathematics Questions on Odd one Out

The value of \( 1 + \sec 19^\circ \sin 71^\circ \) is:
What is the value of \( \csc 31^\circ \sec 59^\circ \)?
$\cot(90^\circ - \theta) = ?$
The value of \( \frac{1 - \tan^2 45^\circ}{1 + \tan^2 45^\circ} \) is:
How many odd days are there in 100 years?
Number of odd days's up to the year 2000
Odd one out 10, 26, 21, 24, 18