Alarge retail company has 500 stores in the united states and 300 stores in europe. the average number of employees per store is 200, for a total of 100,000 employees in the united states and 60,000 employees in europe. the company is considering offering employees one of two new benefits - one additional day of paid vacation per year or a small increase in pay. a survey will be given to a sample of employees to investigate which benefit is preferred and whether there is a difference in preference between employees in the united states and employees in europe.