answer with full explanation

Suppose that the life of an appliance has an exponential distribution with mean 4 yrs. The warranty return; 100% of the price if the appliance fails in the rst year, 75% of the price if it fails in the second year, 50% of the price if it fails in the third year, and nothing after that. What is the expected value of the payment on the warranty if the appliance costs $5000