Calculus I Math 250

Ex 5. Sand falls from an overhead bin7 accumulating in a conical pile with a radius that is always three times its height. If the sand falls from the bin at a rate of 120 ft3/mz'n, how fast is the height of the sand pile changing when the pile is 10 ft high? Ex 6. An observer stands 200 meters from the launch site of a hotair balloon. The balloon rises vertically at a constant rate of 4 m / 5. HOW fast is the angle of elevation of the balloon increasing 30 seconds after the launch? (The angle of elevation is the angle between the ground and the observer's line of sight to the balloon. Approximate all answers to 3 decimal places)