The correct answer is 
D. Groups and Families
I did the quiz nd this was the right answer
Hopes this helps :)
 
        
                    
             
        
        
        
Answer:
the time it takes for one complete back and forth swing 
Explanation:
the Mark's is showing you the time it swings back and forth 
 
        
             
        
        
        
Answer:29.627 m
Explanation:
Given
Initial velocity of life preserver(u) is 1.6 m/s
it takes 2.3 s to reach the water 
using equation of motion
v=u+at

v=24.163 m/s
Let s be the height of life preserver



s=29.627 m
 
        
             
        
        
        
I think its b too but i may be wrong
        
             
        
        
        
3. is the answer, <span>Sodium needs to lose one electron, and chlorine needs to gain one electron. This is because Sodium's row always wants to give away an electron, while Chlorine's row wants to gain an electron.</span>