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PROBLEM BACKGROUND (contains no data to solve the problem) Some drugs need to be provided to the bloodstream continuously over an extended period of time. One method of doing this is with drug reservoir which is attached to the skin with an adhesive as shown. The best-known example would be the nicotine patch used to deliver nicotine to the bloodstream to help people quit smoking. PROBLEM STATEMENT A nicotine patch provides a constant concentration of nicotine to the surface of the skin of 2.0 mol/m3. The nicotine then diffuses through the skin through the epidermis (0.01 cm thick) and The Layers of Skin dermis (0.2 cm thick) to the subcutaneous tissue where the nicotine is taken into the bloodstream. Epidermis a) Calculate the time it takes for the nicotine to reach 12% of the surface value at the interface between the epidermis and dermis (0.01 cm from the surface). Subcutaneous b) What is the concentration at the interface between the dermis and subcutaneous tissue at the time found in part a)? Potentially helpful information: Diffusivity of nicotine in the dermis and the epidermis is 1 x 107cm/s. Dermis tissue