Science and Technology Crossword 4

Click on a number in the crossword, write your answer, and then click "Enter". (Click "Hint" if you need help to get the next letter in each word.)
1    2     3   4    
     5    6   
7        8    
     9     
        
10      11      
        
12          

Across

1. Computer screen
5. Total amount
7. It consists of photons
8. Sodium's symbol
10. The Big Bang began it
12. Force or power

Down

1. Group of bonded atoms
2. Less than zero
3. Operating System
4. We need cars that _ _ _ on electricity.
6. A piece of iron that attracts iron
9. Type of graph
11. Unit of '12 across'