9.5 Hypothesis Testing for Proportions Using the p-Value (Z-test) A well-known brokerage firm executive claimed that 60% of investors are currently confident of meeting their investment goals. An XYZ Investor Optimism Survey, conducted over a two week period, found that in a sample of 400 people, 57% of them said they are confident of meeting their goals. Test the claim that the proportion of people who are confident is smaller than 60% at the .02 significance level. a.) The null and alternative hypothesis would be: Ho: / 0.6 Ha: M 0.6 Ha:p / 0.6 Ha:p