Information regarding the defined benefit pension plan of Tri Cities Transport included the following for 2021 ($ in millions): $48 Service cost Interest cost Actual and expected return on plan assets Amortization of net gain-AOCI Amortization of prior service cost-AOCI Retiree benefits paid (end of year) What is Tri Cities' pension expense for 2021? Multiple Choice $98 million $56 million $62 million $164 million