Answer:
8) B
9) D
*ASSUMING THE ALPHA-LEVELS FOR THESE PROBLEMS IS .05.*
Explanation:
8) Left-tailed test means that the alternate hypothesis is x is less than a certain value. The p-value, on the calculator, is normalcdf(-999, -1.83) if it's left-tailed, which is .0336. In that case, we would reject the null hypothesis, because the alpha-level is above our p-value.
9) Two-tailed test means that the alternate hypothesis is x does not equal a certain value. The p-value for this, on the calculator, is normalcdf(1.95,999) times two, because we need both tails. In this case, we would fail to reject the null hypothesis, assuming our alpha-level is .05.
- normalcdf(1.95,999) = .0256*2 = .0512.