What happened when the wheel was invented?

A river should be crossed by a father, a mother and their two sons and two daughters.
There are some rules that should be followed while crossing the river. There can be only two people in the raft while crossing. The daughters cannot be with their father unless there is the presence of the mother. The sons cannot be with their mothers unless the father is present. Unless the guard is on the board, the criminals cannot be with any of the family members. Only the adults like the father, the guard, and the mother knows to use the raft.

How will they cross the river?

Below the four parts have been reorganised. The four partitions are exactly the same in both arrangements. Why is there a hole?

Nine marbles are arranged in the image below. Can you slide two marbles to form a square?

A train full of passengers goes through a tunnel. When the train comes out from the other end, there is no single person on the train.

How did it happen?

Can you find out the missing number in the grid?

Steffi's daughter Jazelle needs to be picked up from school every day.
Steffi asks one of her colleagues to pick up Jazelle from the school. Steffi devised a password system to confirm that Jazelle goes with the correct colleague only.

The password on Monday was SJM16.
The password on Wednesday was TAW39.

What will the password be for Friday?

What Time Should the last watch show in the below figure?

It has a long neck, A name of a bird, Feeds on cargo of ships, It's not alive,

What is it?

Can you find the missing piece of the Porsche?