The tear film (of density 1 g/cm' and viscosity 0.013 g/cm per s) bathes the comea and protects it from drying out. Treat the cornea as a vertical planar surface, and assume that the tear film has a uniform thickness of h= 5 um. Let the length of the cornea (in the flow-wise direction) be 1 cm. Assume that a blink occurs every 5 s (which replenishes the fluid layer on the surface of the cornea). (a) Find what fraction of the tear film is lost between blinks (assume steady flow between blinks). (b) The surface of the tear film has proteins that alter the surface tension. Owing to their presence, a Marangoni force can develop. This force can be modeled by assuming that the surface of the tear film become immobile. How would this alter your answer to part (a)? Tear film Cornea Q Air y=0 y=h