18. Stress at work:In a poll conducted by the General Social Survey, 81% of respondents said that their jobs were sometimes or always stressful. Two hundred workers are chosen at random.

a.Approximate the probability that 160 or fewer find their jobs stressful.

Given that p=0.81 and n = 200

We have to findP(X160)=P(z

b. What would be the mean and standard deviation of your distribution?How would you adjust the 150 value to account for using the normal distribution to approximate your result?Using those values, what would be the z-score?

JUST NEED b answered please!