#20 Help ​

a)  A decline of 10%  per year  means that the common ratio between terms  is ⇒  r  = .9

So.....geometric

b) aⁿ  =  1250 (.9)^n-1     where n  is the value at the beginning  of the nth year

c)  6th year   =   1250 (.9) ^{6 - 1}   =  1250 (.9)⁵  = $738.11