Question

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Answer 1

$b_{1} =2\\\\b_{2}=6\\\\b_{2}=b_{1}*q\\\\q=\frac{b_{2}}{b_{1}}=\frac{6}{2}=3\\\\b_{8}=b_{1}*q^{7}=2*3^{7}=4374\\\\\boxed{b_{8}=4374}\\\\\\S_{7} =\frac{b_{1}(q^{7} -1)}{q-1}=\frac{2*(3^{7}-1) }{3-1}=2187-1=2186\\\\\boxed{S_{7}=2186}$