The American Management Association wishes to have information on the mean income of store managers in the retail industry. A random sample of 256 managers reveals a sample mean of $45,420. the standard deviation of this population is $2050. You need to construct 90%, 95% and 99% CIs for the mean income of the population. Which CI is the widest?

99% CI

I don't have enough information to decide.

90% CI

95% CI