<span>7 electrons in each outer shell 
Group 17 
Most reactive 
Fluorine, Chlorine, Bromine, Iodine, Astatine 
Alkali Metals: 
1 electron is each outer shell 
Group 1 
Also reactive, but not as much as the halogens 
Lithium, Sodium, Potassium, Rubidium, Cesium, Francium </span>
        
             
        
        
        
Answer: the answer is seedstock
 
        
             
        
        
        
Explanation:
The most common and fastest way of measuring ocean depth uses sound. Ships using technology called sonar, which stands for sound navigation and ranging, can map the topography of the ocean floor. The device sends sound waves to the bottom of the ocean and measures how long it takes for an echo to return.
 
        
             
        
        
        
cell membrane is a biological membrane that separates the interior of all cells from the outside environment. 
so c