Boxplots display ______.

a.a sense of center only

b. a sense of center, variability, and shape

c. none of the choices provided

d. boxes

When the sample mean equals 25 and the sample standard deviation equals 5, the standardized value of 15 equals ______.

1. 2.00
2. -2.00
3. 3.00
4. -3.00