6. A spherical balloon is being inated at the rate of 30 1':_;]_ At what rate is the radius changing at the moment in time, when the radius has reached has reached 10 m? Assume that the radius is zero initially. 4:25 PM Wed Dec 15 7::- '5' @18%@ . coursesmaineedu Mat 152 Final Exam Review Problems m Page 3 of 11 3. You are to build a rectangular pen with three parallel partitions using 500 feet of fencing. What dimensions will maximize the total area of the pen? 4. You are to construct a closed cylindrical can with the volume of 1 liter = .001m3. If material for the top and bottom costs $3 per 1%2 and material for the sides costs $2 per m2, What dimensions will result in the least expensive can? What is the minimum cost