The following data relate to a defined benefit pension plan for Hollistir Co. PBO Jan. 1, 2020, not including any items below.. . . . PSC from amendment dated Jan. 1,2020, (10 years is the amortization period) .. .. . . Gain from change in actuarial assumptions, computed as of Jan. 1, 2020..... . . . 20,000 .. . .. 0,000 . . ....3.000 **....4,000 8% 10% Expected rate of return on plan assets....................... .. Required a. Compute pension expense for 2020. Hollistir amortizes the full pension gain/loss over average service life of 15 years, using the straight-line method b. Compute the PBO at December 31, 2020. c. Compute fair value of plan assets at December 31, 2020