If Atul finds that he is twelfth from the right in a line of boys and fourth from the left, how many boys should be added to the line such that there are $28$ boys in the line?

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?
$1, 2, 3, 4, 2, 3, 1, 4, 4, 3, 2, 2, 1, 2, 4, 3, 1, 4, 4, 1, 2$

Madhu is $18^{th}$ from the left end and Sandhu is $11^{th}$ from the right end of a row of $40$ children. How many children are there between Madhu and Sandhu in the row?

If the first and second digits in the sequence $5, 9, 8, 1, 3, 2, 7, 4, 3, 8$ are interchanged,also the third and fourth digits,the fifth and sixth digits and so on,which digit would be the seventh counting to your left?

How many even numbers are there in the following sequence of numbers which are immediately followed by an odd number as well as immediately preceded by an even number?
$8, 6, 7, 6, 8, 9, 3, 2, 7, 5, 3, 4, 2, 2, 3, 5, 5, 2, 2, 8, 1, 1, 9$

How many days will there be from $26^{th}$ January,$1988$ to $15^{th}$ May,$1988$ (both days included)?