The back - office staff of an investment company are required to start their day at the office by 7 : 30 a . m

The back$-$office staff of an investment company are required to start their day at the office by $7$:$\mathrm{30}$ a$.$m$.$ Once at work, the employees follow a precise set of procedures as they complete their tasks. The jobs of the back$-$office staff $\_\_\_\_\_\_\_\_$