Einstein Companys defined benefit pension plan specifies annual retirement benefits equal to: 1.3% service years final years salary, payable at the end of each year. Mary Thompson was hired by Einstein at the beginning of 2008 and is expected to retire at the end of 2037 after 30 years service. First pension payment would be at the end of 2038. Her retirement is expected to span 20 years. Thompsons salary is $200,000 at the end of 2017 and the companys actuary projects her salary to be $450,000 at retirement. The actuarys discount rate is 4%. At the beginning of 2018, the pension formula was amended to: 1.5% service years final years salary. The amendment was made retroactive to apply the increased benefits to prior service years. What is the Companys prior service cost at the beginning of 2018 with respect to Thompson after the amendment?

a. $58,055 b. $55,822 c. $60,377 d. $61,235