Answer: Both of the compounds contain primary bonding; however, the bonding is of different types. Magnesium chloride (MgCl₂) contains ionic bonds, which are stronger and involve the complete transfer of electrons. Meanwhile, ethane (C₂H₆) also bonds by electron transfer but the electrons are not completely transferred from one atom to another. Instead, they are shared, forming what is known as a covalent bond.  
 
        
             
        
        
        
That's THERMAL energy, often referred to as "heat".
        
             
        
        
        
The magnitude of Alioth ( the brightest star in the big dipper ) is 1.76 and it is about 81 light years distant from Earth. 
        
                    
             
        
        
        
Answer:

Explanation:
The density changes means that the length in the direction of the motion is changed.
Therefore, 

Given :
Side,  b = h = 0.13 m
Mass, m = 3.3 kg
Density = 8100 
So, 


l = 0.024 m
Then for relativistic length contraction, 







Therefore, the speed of the observer relative to the cube is 0.9833 c (in the units of c).