The manager of Colonial Furniture has been reviewing weekly advertising expenditures. During the past 6 months, all advertisements for the store have appeared in the local newspaper. The number of ads per week has varied from one to seven. The store’s sales staff has been tracking the number of customers who enter the store each week. The number of ads and the number of customers per week for the past 26 weeks were recorded. Determine the sample regression line.

Calculate the residuals and predicted values of y in Exercise 16.3.

Refer to Exercise 16.2. Calculate the residuals and the predicted values of y.

Besides their known long-term effects, do cigarettes also cause short-term illnesses such as colds? To help answer this question, a sample of smokers was drawn. Each person was asked to report the average number of cigarettes smoked per day and the number of days absent from work due to colds last year. Determine the regression line

You are given the following six points:

$$\begin{array}{rrrrrrr}x & -5 & -2 & 0 & 3 & 4 & 7 \\ y & 15 & 9 & 7 & 6 & 4 & 1\end{array}$$

Determine the regression equation.

Caffeine

$$(C_8H_{10}N_4O_2)$$

is a stimulant found in coffee and tea. If a solution of caffeine in the solvent chloroform

$$(CHCl_3)$$

has a concentration of 0.0500 m, calculate the percentage of caffeine by mass.

A club has 25 members. a) How many ways are there to choose four members of the club to serve on an executive committee? b) How many ways are there to choose a president, vice president, secretary, and treasurer of the club, where no person can hold more than one office?

Sally Johnson loaned a friend $10,000 at 15% interest, compounded annually. The loan will be paid in four equal end-of-year payments. Sally expects the inflation rate to be 3%. After taking inflation into account, what rate of return is Sally receiving on the loan? Compute your answer to the nearest 0.1%.

What is the variance of the number of heads that come up when a fair coin is flipped 10 times?

A scientist begins with 100 milligrams of a radioactive substance that decays exponentially. After 35 hours, 50 mg of the substance remains. How many milligrams will remain after 54 hours?

(a) Calculate the electric potential 0.250 cm from an electron. (b) What is the electric potential difference between two points that are 0.250 cm and 0.750 cm from an electron? (c) How would the answers change if the electron were replaced with a proton?

A 5.00-g bullet is fired horizontally into a 1.20-kg wooden block resting on a horizontal surface. The coefficient of kinetic friction between block and surface is 0.20. The bullet remains embedded in the block, which is observed to slide 0.230 m along the surface before stopping. What was the initial speed of the bullet?

What minimum horsepower must a motor have to be able to drag a 310-kg box along a level floor at a speed of 1.20 m/s if the coefficient of friction is 0.45?

What is one way within subjects ANOVA?