Answer
1.59
Work Step by Step
Use the lensmaker’s equation.
$$\frac{1}{f}=(n-1)(\frac{1}{R_1}+\frac{1}{R_2})$$
$$n=1+\frac{1}{f}(\frac{R_1R_2}{R_1+R_2})$$
$$n=1+\frac{1}{28.9cm}(\frac{34.1cm}{2})=1.59$$
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