A firm is concerned about the market-share of its products. In the past, about 35% of households used their product. Has this increased? To test this, they set up the following:
H0: p <= 0.35
H1: p > 0.35
To carry out the test at a significance level of 4%, an analyst took a random sample of households (sample size = 80), and found the sample proportion of households that used their product, and it was 28 out of 80. From this, the appropriate Z-stat was computed. What is the critical value for this Z-stat?