Explain what causes the length of the shadow to change during the day.

As the day goes by, the Earth moves. When the Earth moves/rotates, the direction of where the sun is moves too. So in the morning, the sun could be on the right, casting a long shadow to the left, while during noon, the sun is high above, and your shadow is basically underneath you.

He want to contact the red cross/red crescent because they are the main non profit organization that deals with disasters around the world