Solution:
Principal =P= $ 7,500
Option A→(Simple interest)
Rate of interest= R=4%
Time( )=4 years
)=4 years
Time( )=6 years
)=6 years
Amount= Principal + Interest(Simple or compound interest)
Formula for Simple interest


Total amount after 4 years when interest is simple= 7500 +1200= $ 8700
Total amount after 6 years  when interest is simple= 7500 +1800= $ 9300
Option B
Formula for amount(A) when interest is 3.15% compounded annually.



Total amount after 4 years when interest is compounded annually=$ 8491 (approx)
Total amount after 6 years  when interest is compounded annually=$ 9034(approx)
 
        
                    
             
        
        
        
The square root of 100 is 10
        
             
        
        
        
For this case we have that by definition, the density is given by:

Where:
M: It is the mass
V: It is the volume
According to the data of the statement we have:

So, the mass is given by:

Thus, the mass of the brass ornament is
Answer:
