A two$-$day environmental clean up started at $9$AM on the first day. The number of workers fluctuated as shown in the following figure.

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Suppose that the workers were paid $11$ dollars per hour for work during the time period $9$ am to $5$ pm and were paid $16\mathrm{.}5$ dollars per hour for work during the rest of the day. What would the total personnel costs of the clean up have been under these conditions?

total cost $=$ dollars