Question 914104
 A bright light on the ground illuminates a wall 12 meters away. A man walks from the light straight toward the building at a speed of 1.1 m/s. The man is 2 meters tall. When the man is 4 meters from the building, how fast is the length of his shadow on the building decreasing? (Give your answer correct to two decimal places.)
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Similar to the boat problem.
Get the length of the shadow in terms of his distance from the building, that's just geometry.
Differentiate wrt time, etc.
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