已知等差数列{a n }的公差为d,a 3 =5,a 5 =9,等比数列{b n }的公比为q,b 1 =1,b 4 =27,设S n =a 1 b 1 +a 2 b 2 +a 3 b 3 +…+a n b n ,T n =a 1 b 1 -a 2 b 2 + a 3 b 3 -…+(-1 ) n-1 a n b n (n∈N + ). (1)求S 3 和T 3 的值; (2)设f(n)=(1-q)S 2n -(1+q)T 2n ,求f(n)的表达式.
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【判断题】Trade creation is the volume of trade that is redirected from low-cost exporters to higher-cost trade bloc member countries.