The schoolboard in Alief ISD wants to assess support for a new bond which will be used to update and improve the schools in the district. The taxpayers in the community pay for the bond over an extended period of time. Without their support, the bond will not pass. The district surveys a random sample of 1,500 Alief residents and find that 740 of them would support the bond.

(a) Construct and interpret a 95% confidence interval to estimate the proportion of residents who support the bond.

(b) Interpret the confidence level of 95%.

(c) The survey also asked for information on annual household income. The sample average was $44,340 with a standard deviation of $10,800. Construct and interepret a 99% confidence interval to estimate the true average annual household income in this district.