The change in distance is 30 because if you subtract both number you'll get 30
        
                    
             
        
        
        
I like playing basketball. So I'm the object in motion. Until an unbalanced force comes and hits me I fall and stay at rest. 
        
                    
             
        
        
        
The correct matches are as follows:
<span>1. first nuclear reactor 
</span>Fermi - an italian physicist who made the first nuclear reactor<span>
2. </span>1/0 η<span>
 </span>atomic mass <span>
3. decaying nuclei 
</span>fission<span> - nuclear reaction from a heavy elements to lighter elements
4. number of neutrons and protons 
</span>neutron <span>
5. builds heavier elements 
</span>fusion - nuclear reaction from two or more elements to a heavier element<span>
6. discovered radioactivity 
</span>Curie<span>
7. unit of radiation 
</span> Becquerel  
        
                    
             
        
        
        
Speed, the toy can calculate a persons speed