Which number should replace the question mark?

How many Watermelons are there in the below picture?

What is wrong in the below Picture?

A bomb exploded in a room full of married couples and no one died. How?

The husband and wife were jogging in the morning. To match every two steps of the husband, the wife required three steps. If Both of them start with the here right foot. After how many steps do their left foot be together?

How many people must be gathered together in a room, before you can be certain that there is a greater than 50/50 chance that at least two of them have the same birthday?

What is the four-digit number in which the first digit is one-third the second, the third is the sum of the first two, and the last is three times the second?

I am a type of room you cannot enter or leave. Raised from the ground below, I could be poisonous or a delicious treat. What am I?

What part of the chicken has the most feathers?

A Doctor always sneezes before the rain. Doctor sneezes, Will it rain?