please provide working out to the following question:

Mary and Steve are in their 40 s. Mary works part-time and earns $40,000 per year, while Steve is the primary breadwinner with an annual salary of $120,000. They have one child and have saved $20,000. Concerned about their financial well-being if Steve were to pass away prematurely, they are evaluating the trade-off between self-financing their risk by investing their savings and purchasing a term life insurance policy. Q1 Part (a) Using the multiple's approach, calculate the appropriate amount of life insurance coverage needed to provide Mary with a perpetual annual income of $80,000, should Steve pass away. Use a discount rate of 5%