2.A global financial institution transfers a large data file every evening from offices around the world to its London headquarters. Once the file is received, it must be cleaned and partitioned before being stored in the company's data warehouse. Each file is the same size and the time required to transfer, clean, and partition a file is normally distributed, with a mean of 1.5 hours and a standard deviation of 15 minutes.

a.If a manager must be present until 85% of the files are transferred, cleaned, and partitioned, how long will the manager need to be there?

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