The set is not closed
Example 
-4 * -2 = 8
8 is not a negative integer
 
        
             
        
        
        
Answer:
wym by 4 decimal places
Step-by-step explanation:
 
        
             
        
        
        
Pound is the unit of measure of passengers car weight
According the statement 
The weight of passengers car is 4.5 times 10 superscript 3 units.
from this it is clear that the in simple terms the weight become 4.5 * 10^3
AND
the term 10^3 is used when we measure the weight in pounds.
So, Pound is the unit of measure of passengers car weight.
Learn more about WEIGHT here brainly.com/question/2337612
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