How many $18$s are there in the following sequence which are immediately preceded by $9$ but not immediately followed by $7$?
$7, 1, 9, 1, 1, 7, 1, 8, 9, 1, 7, 1, 2, 1, 3, 1, 4, 5, 7, 1, 3, 9, 1, 7$

Three persons $A, B$ and $C$ are standing in a queue. There are $5$ persons between $A$ and $B$ and $8$ persons between $B$ and $C$. If there are $3$ persons ahead of $C$ and $21$ persons behind $A$, what could be the minimum number of persons in the queue?

The Managing Director entered the conference room $10 \, \text{minutes}$ before $12:30 \, \text{hours}$ for interviewing. He came $20 \, \text{minutes}$ before the chairman who was $30 \, \text{minutes}$ late. At what time was the interview scheduled?

Some boys are sitting in a row. $P$ is sitting fourteenth from the left and $Q$ is seventh from the right. If there are four boys between $P$ and $Q,$ how many boys are there in the row?

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

How many $6$'s are there in the following series of numbers which are preceded by $7$ but not immediately followed by $9$?
$6, 7, 9, 5, 6, 9, 7, 6, 8, 7, 6, 7, 8, 6, 9, 4, 6, 7, 7, 6, 9, 5, 7, 6, 3$