26. [-/1 Points] DETAILS SERCP11 22.7.P.044. MY NOTES ASK YOUR TEACHER PRACTICE ANOTH A boy floating on a pond watches a fish swim away from him as in the figure below. If the fish is 2.11 m beneath the surface, for what maximum distance d (in m) will he be able to see the fish? Neglect the height of the boy's eyes above the water. HINT 2.11 m m27. [-/2 Points] DETAILS SERCP11 22.A.P.047. MY NOTES ASK YOUR TEACHER PRACTICE ANO When a man stands near the edge of an empty drainage ditch of depth 2.80 m, he can barely see the boundary between the opposite wall and bottom of the ditch as in Figure (a) shown below. The distance from his eyes to the ground is h = 1.80 m. (Assume 0 = 27.90.) 2.80 m a O b O (a) What is the horizontal distance d from the man to the edge of the drainage ditch? d = (b) After the drainage ditch is filled with water as in Figure (b) shown above, what is the maximum distance x the man can stand from the edge and still see the same boundary? X = m28. [-/1 Points] DETAILS SERCP11 22.A.P.052. MY NOTES ASK YOUR TEACHER PRACTICE ANOTHER Endoscopes are medical instruments used to examine the gastrointestinal tract and other cavities inside the body. The light required for examination is conducted from an outside source along a long, flexible bundle of optical fibers to the tip, where it exits and illuminates the internal cavity. A lens on the tip collects an image of the lighted cavity and another fiber bundle conducts the image back along the endoscope to an eyepiece for viewing (see the figure below). If each fiber in the bundle has diameter d = 1.09 x 107# m and refractive index n = 1.39, find the smallest outside radius R (in m) permitted for a bend in the fiber if no light is to escape. HINT Eyepiece Light Tip of endoscope R m