Answer:
If you meant the Periodic Table it's the alkaline-earth metal
beryllium (Be) 
magnesium (Mg)
calcium (Ca)
strontium (Sr)
barium (Ba)
radium (Ra)
Explanation:
 
        
             
        
        
        
Distance, since distance represents how far something has travelled, which would be in our case 2.5m.
        
                    
             
        
        
        
Answer:
Answers at the bottom!!
Explanation:
For the first answer: Gamma ray
Gamma rays and x-rays consist of high-energy waves that can travel great distances at the speed of light and generally have a great ability to penetrate other materials. For that reason, gamma rays (such as from cobalt-60) are often used in medical applications to treat cancer and sterilize medical instruments.
For the second answer: They both have technological uses.
In my opinion I'm pretty sure it's A because we do use microwaves and x-rays as technological uses.
Hope this helps!!
Happy Holidays and Season Greeting!!
ii Feliz Navidad a todos !!