What is a standard normal distribution

Question

Complete the mcq:

1. If P(A) = 0.4, P(B| A) = 0.35, P(A  B) =0.69, then P(B) =

a. 0.14
b. 0.43
c. 0.75
d. 0.59

2. If X and Y are mutually exclusive events with P(X) = 0.295, P(Y) = 0.32, then P(XY) =

a. 0.0944
b. 0.6150
c. 1.0000
d. 0.0000

3. For a standard normal distribution, the probability of z  0 is

a. zero
b. -0.5
c. 0.5
d. one

4. Z is a standard normal random variable. The P(-1.96  Z  -1.4) equals

a. 0.8942
b. 0.0558
c. 0.475
d. 0.4192

5. The weight of football players is normally distributed with a mean of 200 pounds and a standard deviation of 25 pounds. The probability of a player weighing less than 250 pounds is

a. 0.4772
b. 0.9772
c. 0.0528
d. 0.5000

6. A population has a standard deviation of 16. If a sample of size 64 is selected from this population, what is the probability that the sample mean will be within 2 of the population mean?

a. 0.6826
b. 0.3413
c. -0.6826
d. Since the mean is not given, there is no answer to this question.