Which represents the series 1+1/3+1/9+1/27 using sigma notation?

Can somebody me out with this question

In a sample of 200 residents of georgetown county, 120 reported they believed the county real estate taxes were too high. develop a 95 percent confidence interval for the proportion of residents who believe the tax rate is too high. (round your answers to 3 decimal places.) confidence interval for the proportion of residents is up to . would it be reasonable to conclude that the majority of the taxpayers feel that the taxes are too high?

Aboat costs 19200 and decreases in value by 12% per year. how much will it cost in 5 years