What does this rebus mean?

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TIME

Luis Garavito killed Density x Volume.

Who is Luis Garavito ?

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

What is it?

Find the 8 in the below-given Image.

A mad serial killer kidnaps people and forces them to play the game of 2 pills with them, In this game, there are pills in the table and one of them is normal pill while the other one is deadly poisonous.
The victim will choose one pill and the killer will pick the other pill and both simultaneously will swallow the pill with water.
victim dies every time.

One day the serial killer kidnaps the Joseph and forces him to play the same game with him.

Joseph solves the mystery of the two pills and remains alive.

Explain?

A guard is positioned at the one side of the bridge saying ‘A’. His task is to shoot all those who try to leave from ‘A’ to the other side and say ‘B’. He also need to welcome the person who comes from another side ‘B’ to his side ‘A’. The guard comes out of his post every 1 hour and looks down the bridge for any people trying to leave. You are at side ‘A’ and wish to go to another side ‘B’. you also know that it would take 1:45 hr to cross the bridge. How will you cross the bridge?

You may enter, but you may not come in. I have space, but no room. I have keys, but open no lock. What am I?

A Monkey, a squirrel, and an Eagle are racing to the top of the mango tree. Assuming all these animals are in perfect shape, Which animal will reach to Banana first?

The LCD device should be able to tell the right time in the format HH:MM: SS in a 12-hour format. You can refer to the picture to get an idea. The device is a simple "level indicator" which has to be converted into a watch. How will you program it to work?

A shepherd had 18 sheep, out of which, all but ten died.

Can you tell us how many sheep was he left with?