tje average acceleration of the car is 

the average acceleration of the car is 1.4 m/s
 
        
             
        
        
        
A pulsar has the strongest magnetic field
        
                    
             
        
        
        
Not sure the precise concept of "normal observation", but I assume that is observed by "eyes".
Eye observation is basically macroscopic, but when you use a mark, which can be regarded as a point of mass, then it goes to microscopic.
Mark is a reference point which you can compare the relative position change, but with your eyes, first you cannot notice microscopic changes, second the eyes cannot precisely set a stable reference point.
        
                    
             
        
        
        
An ice cube would transfer heat to another object whose temperature
is lower than zero°C (32°F).
A block of "dry ice" is sitting there at a temperature of -78°C (-109°F).
An ice cube helps to melt dry ice nice and fast.
If you could find a block of solid nitrogen, its temperature would be
63K (-210°C, -346°F).  An ice cube would transfer heat to that baby 
so fast that it would instantly boil.
        
             
        
        
        
I believe it would be weight. mass never changes.