John Jackson makes the following offer to his two sons, Dave and Thomas. He says that each of them is to submit a written request for an amount that they want (in whole dollars). They can request $0. Let $D (respectively, $T ) denote the amount requested by Dave (respectively, Thomas). Each son is to decide on the amount to request without the knowledge of the amount requested by the other brother. If D+T20, then they get their requested amounts. In addition, John Jackson doublesthe remaining amount, 20DT , and splits the doubled amount equally between the two brothers. If D+T>20, then both get zero dollars.

Is D=20,T=20 a Nash equilibrium?