A company has old mixer purchased 14 years ago for 306,469 and has a current market value of 60,000 AED that will decline 30% each year thereafter. The expected O&M costs of 20,000 in the first year that are expected to increase by 30% per year thereafter. This mixer can be used for another four years. a) Determine the economic service life of the old mixer at i=10% b) A challenger with an ESL of 7 years and annual equivalent costs of 47,000 per year has been identified, when should the replacement occur? A company has old mixer purchased 14 years ago for 306,469 and has a current market value of 60,000 AED that will decline 30% each year thereafter. The expected O&M costs of 20,000 in the first year that are expected to increase by 30% per year thereafter. This mixer can be used for another four years. a) Determine the economic service life of the old mixer at i=10% b) A challenger with an ESL of 7 years and annual equivalent costs of 47,000 per year has been identified, when should the replacement occur