A work center operates for 150 hours, and the actual production during that time is equivalent to 120 hours of work. Calculate the utilization of the work center.  

 A work center completes 80 units in a shift, while the standard for that item is set at 90 units per shift. Determine the efficiency of the work center.  

 A manufacturing facility has a machine with 450 available hours for production in a given month. During this period, the machine operates for 380 hours, generating output equivalent to 350 hours of work. Calculate the productivity of the machine.