1. (24 points) True or False. All credits are assigned to explanations. (a) In a second-price sealed-bid auction, the only Nash equilibrium is for every buyer to bid their true valuation. (b) In a Spence job market signalling equilibrium, if the employers believe the applicant is of the high type when the applicant chooses eduction level 6, they must also believe that the applicant is of the high type if the applicant chooses education level 6' > e