4. The Henry Street Mission uses volunteers to assemble care packages for needy families during the holiday season. The mission would like to organize the work as efficiently as possible. A list of tasks, task times, and precedence requirements follows:

a. If the mission wants to complete a care package every 10 minutes, how many volunteers should be called in? Balance the line and calculate the efficiency. How many packages can be assembled in a four-hour period?

b. Suppose that volunteers are plentiful. Balance the line to maximize output. What is the efficiency of the line?

Task Precedence Time (mins) 6 A 3 C B D B 5 E C, D 4 F E 5 AB