Which of the following is the formula in solving finite geometric series. Sₙ = a₁(1+rⁿ)/ (1-r) Sₙ = a₁(1-rⁿ)/ (r-1) Sₙ = a₁(1-rⁿ)/ (1-r) Sₙ = a₁(1-rⁿ)/ (1+r)​