A recent study focused on the number of times men and women send a Twitter message in a day. The information is summarized here:    Sample Size Sample Mean Population Standard Deviation Men 31 29 5 Women 36 34 10 At the 0.01 significance level, we ask if there is a difference in the mean number of times men and women send a Twitter message in a day. Assume that women are Population 1 and men are Population 2. What is the value of the test statistic for this hypothesis test?   a. 2.907   b. 2.641   c. 2.815   d. 2.911

Exercise A4 Why is a bar chart the best way illustrate comparisons?

Exercise B6 What is a substitution effect?

Exercise D21 What are some reasons that the economy might be in a recession, and what is the appropriate government action to alleviate the recession?

Exercise D22 What should the government do to relieve inflationary pressures if the aggregate expenditure is greater than potential GDP?

Savings-Mart (a chain of discount department stores) sells patio and lawn furniture. Sales are seasonal, with higher sales during the spring and summer quarters and lower sales during the fall and winter quarters. The company developed the following quarterly sales forecasting model: Y t=8.25+0.125t2.75D1t+3.50D3t where Y t=predictedsales(million)inquartert 8.25=quarterlysales(million)whent=0 t=timeperiod(quarter)wherethefourthquarterof2002=0,firstquarterof2003=1,secondquarterof2003=2,... D1t={1forfirst-quarterobservations0otherwiseD2t={1forsecond-quarterobservations0otherwiseD3t={1forthird-quarterobservations0otherwise Forecast Savings-Marts sales of patio and lawn furniture for each quarter of 2010.

Exercise B2 Why do indifference curves slope down?

Exercise B3 Why are indifference curves sleep on the left and flatter on the right?

Exercise D18 How do economists use the multiplier?

Exercise B7 What is an income effect?