Employees were observed at one of two high-tech companies for more than 1000 hours (Mark, Gonzalez, & Harris, 2005). The employees spent just 8 minutes, on average, on one project before being interrupted. Moreover, after each interruption, they needed an excessive amount of time to get back to the original project. So maybe the reality is that multitasking (interruptions during work) reduces overall productivity. Test hypothesis at a=0.01