Which of the following is true regarding the Nash equilibrium concept? Select one: O a. firms interacting with each other don't trust each other O b. once competitors choose a mutual strategy, any change from that strategy will make one worse off O c. once competitors choose a mutual strategy, neither can gain by changing their strategy O d. all of the aboveRequiring consumers to purchase a certain good bundled with the purchase another good could be considered illegal if Select one: Q a. the firm earns positive economic profits from that sale 0 b. other firms are not able to sell their product because of the sale of the bundled product 0 c. consumers like one of the goods more than the other good within the bundle Q d. a low income consumer doesn't have enough money to buy both goods bundled together