The statistics of nequals=22 and sequals=14.3 result in this? 95% confidence interval estimate of sigma: 11.0 less than sigma less than < 20.4. that confidence interval can also be expressed as (11.0, 20.4). given that 15.7 plus or minus ±4.7 results in values of 11.0 and 20.4, can the confidence interval be expressed as 15.7 plus or minus ±4.7 as well? choose the correct answer below. a. yes. since the? chi-square distribution is? symmetric, a confidence interval for sigma? can be expressed as15.7plus or minus ±4.7.b. no. the format implies that sequals=? 15.7 but s is given as 14.3. in? general, a confidence interval for sigma? does not have s at the center. c. yes. in? general, a confidence interval for sigma? has s at the center. d. not enough information