In a row of $21$ girls, when Monika was shifted by four places towards the right, she became $12^{th}$ from the left end. What was her earlier position from the right end of the row (in $^{th}$)?

In the series,$6, 4, 1, 2, 2, 8, 7, 4, 2, 1, 5, 3, 8, 6, 2, 1, 7, 1, 4, 1, 3, 2, 8, 6$,how many pairs of successive numbers have a difference of $2$ each?

In a row of $21$ girls, when Anita was shifted by four places towards the right, she became $12^{th}$ from the left end. What was her earlier position from the right end of the row (in $^{th}$)?

If February $1, 1996$ is Wednesday,what day is March $3, 1996$?

Which two months in a year have the same calendar?

In a school,the following codes were used during physical exercise. $1$ means 'start walking',$2$ means 'keep standing',$3$ means 'start running at the same spot',$4$ means 'sit down'. How many times will a student who performs the following sequence without error from the beginning to the end have to sit down?
$1, 2, 3, 4, 2, 3, 1, 4, 4, 3, 2, 2, 1, 2, 4, 3, 1, 4, 4, 1, 2$