Which geometric formula would find the n th term for the sequence 5 , 10 , 20 , 40 ?

Each term is twice the previous term, so the sequence is geometric with first term 5 and common ratio 2. The nth-term formula is aₙ = a₁rⁿ⁻¹, giving aₙ = 5 × 2ⁿ⁻¹. This is choice A, “5 times 2 raised to the n minus 1 power.”

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