$Do$ not round intermediate calculations. $If$ necessary, round the final answer $to4andPowerPoint=10$ per hour and $=20$ per Hour, then $\frac{}{}=0\mathrm{.}5$ per hour$\frac{}{}$ per hour?

A printer requires repair after approximately $10\mathrm{.}5$ hours $of$ use. Failures have been determined

$to$ follow a Poisson distribution. The one technician $on$ duty can fix a printer $inan$ average $of80$

minutes, following $an$ exponential distribution.

What $is\frac{}{}$ per hour?