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Answer:
I think:
a) 4.875%
b) 1170
Step-by-step explanation:
a)
$4000 in 2002 and $3610 in 2004
=> after 2 years, it have lower prices: 4000 - 3610 = $390
$390 in $4000 = 390 : 4000 x 100= 9.75%
It have lower the prices 9.75% after 2 years => each year: 4.875%
b) base on the answers (a), we can guess it in 2008, it have after 6 years => 9.75 * 3 = 29.25%
=> 2008 will be: 4000 x 29.25 : 100 = 1170$