The visit to the National Science Exhibition was a really rewarding experience. Since I was a kid I have been always attracted to science, specifically chemistry, because I have always had a lot of questions about how everything is composed. In the Exhibition I could see many experiments which show in an easy way how to understand chemistry in a simple way, for example I learnt how to turn on a lightbulb with copper and a potatoe.
This event opened my mind and now I am sure I want to be a scientist.
 
        
                    
             
        
        
        
The store display rotates 40 times every half hour meaning that it will rotate 80 times every hour. To find how many times it will rotate in 4 hours, you can do 80 times 4. This is 320 rotations. 
Also, please try and correctly list your question as this does not pertain to this subject. 
        
             
        
        
        
The beam of wood looks like a club or a a staff. It looks like a large olive tree or like a mast of a ship with twenty oars (a very big mast).
Hope this helps :)
        
                    
             
        
        
        
Answer: It symbolizes the support of the United States for West Germany. 
Explanation:
"Ich bin ein Berliner" is a speech delivered by John Kennedy in 1963, in West Berlin. At the time, Kennedy was the United States President. This speech is often considered as the most powerful speech during the Cold War.
In his address, 22 months after East Germany erected the Berlin Wall so that people could not emigrate to the West, Kennedy reminds German people of the United States support at this difficult moment. He expresses solidarity of the United States with West Germany.