The balloon has traveled 30 meters up from the bicyclist and since it's rising 5 meters per second, 2 seconds later it will travel 10 meters higher. 2 seconds later the bicyclist will travel 20 meters away.   so 10+20+30= 60 meters away from each other. 
        
             
        
        
        
<span>valence electrons is our answer cuz i am good at chemstry</span>
        
             
        
        
        
Answer: The atomic weight of silver is 107.87 amu
Explanation:
Mass of isotope silver-107  = 106.91 amu
% abundance of isotope silver -107 = 51.84% = 
Mass of isotope silver-109 = 108.90 amu
% abundance of isotope silver-109  = 48.16% = 
Formula used for average atomic mass of an element :

![A=\sum[(106.91\times 0.5184)+(108.90\times 0.4816)]](https://tex.z-dn.net/?f=A%3D%5Csum%5B%28106.91%5Ctimes%200.5184%29%2B%28108.90%5Ctimes%200.4816%29%5D)

Thus atomic weight of silver is 107.87 amu