True or false: a. All normal distributions are symmetrical b. All normal distributions have a mean of 1.0 c. All normal distributions have a standard deviation of 1.0 d. The total area under the curve of all normal distributions is equal to 1

The manager of the store in the preceding exercise calculated the residual for each point in the scatterplot and made a dotplot of the residuals.
The distribution of residuals is roughly Normal with a mean of $0 and standard deviation of $22.92.
The middle 95% of residuals should be between which two values? Use this information to give an interval of plausible values for the weekly sales revenue if 5 linear feet are allocated to the stores

Explain why t distributions tend to be flatter and more spread out than the normal distribution.

Describe in words the surface whose equation is given. (assume that r is not negative.) $\theta =\frac{\pi }{4}$
a) The plane $y=-z$ where y is not negative
b) The plane $y=z$ where y and z are not negative
c) The plane $y=x$ where x and y are not negative
d) The plane $y=-x$ where y is not negative
e) The plane $x=z$ where x and y are not negative

Seven women and nine men are on the faculty in the mathematics department at a school.
a) How many ways are there to select a committee of five members of the department if at least one woman must be on the committee?
b) How many ways are there to select a committee of five members of the department if at least one woman and at least one man must be on the

The college physical education department offered an advanced first aid course last semester. The scores on the comprehensive final exam were normally distributed, and the z scores for some of the students are shown below: Robert, 1.10 Juan, 1.70 Susan, -2.00 Joel, 0.00 Jan, -0.80 Linda, 1.60 If the mean score was μ=150μ=150 with standard deviation σ=20,σ=20, what was the final exam score for each student?

Each month, households in a certain subdivision generate an average of 10 kg of newspaper for garbage or recycling. Assume the standard deviation is 1.5 kg. If a household is selected at random, find the number of households who were assumed to have between 7 kg and 11.5kg newspaper for garbage or recycling if the certain subdivision has approximately 15,000 households.

C) According to the 2 Standard Deviation Rule, data values that are more than 2 standard deviations away from the mean of the distribution are considered to be "unusually high" or "unusually low."