One of the leading laptop manufacturers has estimated the following demand equation based on the data from its 50 branch offices and dealerships across the country:

Q = + 10,000 - 60P + 300A + 50

0 substitute; significant effect on sales I Choose... ' I demand is inelastic; decreasing price would decrease revenue I [ sales are responsive to advertising to some degree | substitute; insignificant effect on sales [ sales are responsive to competitor's advertising to some degree | normal good and sales are affected much by the business cycle substitute; significant effect on sales normal good and sales are not affected much by the business cycle sales are not responsive to advertising inferior good demand is elastic; decreasing price would increase revenue sales are not responsive to competitor's advertising