Which of the following developed the acceptance theory?

Which of the following measures is used to assess the responsiveness of consumers to advertising expenditures, calculated by dividing the percent change in sales by the percent change in advertising expenses?

A) net sales expenditure B) gross advertising index C) advertising elasticity D) advertising return on investment E) push rating

ERP vendors usually issue a statement of ________ which describes where future development of the product is headed

A) direction B) support C) historical evolution D) vendor upgrades