All departments are of size 9 X 8 a) For the 9 department problem (layout given above), determine the number of units of the material handling system needed for the following data. Vehicle carrying capacity 400ll Tote weight - 10lb Vehicle traveling speed 150ft/min Loading and unloading time -30 seconds Battery charging during planning horizon - 30 minutes Assume rectilinear measures (Centroid-to-Centroid) for calculating material handling distances. Both Pickup and drop off points are located at the center of the departments. Assume Total loaded travel time = total unloaded travel time. b) Redesign the layout to minimize material handling