PLEASE ANSWER ALL THE LETTERS. THANK K YOU

Question 2 Imagine there are two companies A and B. If both don't advertise, each will get $X million. If both advertise, both lower their gain to $3 Million. If A advertises, but B doesn't, A gets $6 million and B only $2 million, and conversely if B advertises and A doesn't. The payoff pattern is shown in the following table. The numbers are in millions of dollars. The rows correspond to the options of player A, and the columns correspond to the options of player B. The entries are payoff for A and payoff for B respectively provided the corresponding options are chosen, separated by a comma. Players' Strategies B advertises B does not advertise A advertises 3, 3 6, 2 A does not advertise 2, 6 X, X (a) Define the concept of a Nash equilibrium. (b)Now assume that 36, will there be a unique Nash equilibrium? If not, then identify all possible Nash equilibria and explain why each of them are qualified as a Nash equilibrium. (d) Compare your equilibrium outcomes in (a) and (b); and explain which one will qualify as a Prisoner's Dilemma game and why