please answer those 11 questions.

1. Assume the muscle is 37oC and is separated from the outside air by layers of fat and skin. The layer of fat, at a particular location on the skin, is 2 mm thick and has a conductivity of 0.16 W m-1 K-1. Above this is a 1.1 mm dermis layer with a thermal conductivity of 0.53 W m-1 K-1. Finally, the outermost epidermal layer is 0.1 mm thick with a thermal conductivity of 0.21 W m-1 K-1. How much heat is lost per unit area and unit time if the ambient air temperature is 0oC?

this is one of the question