Hello I would like to have some help on this thanks if is possible with explanation

Organic Fashion Ltd enters into a 4-year non-cancellable lease agreement starting on 30/6/2017. The following are the provisions of the lease agreement: The fair value of the computerized point of sale system is $179,051 at 30 June 2017. The lease term is for 4 years. The annual lease payments are made in advance with $48,000 due immediately and annual payments of $48,000 on 30 June 2018, 2019, and 2020. The contract specifies that Organic Fashion Ltd specifies a bargain purchase option of $10,000 at the end of the lease term on 30 June 2021. The interest rate implicit in the lease is 8%. The asset's residual value at the end of its 4-year effective useful life is nil. 1-Prove that the interest rate implicit in the lease is: 8%. Item Discount factor Workings 2- Explain the purpose of the implicit interest rate. PV