Cars arrive at a toll gate on a freeway according to a Poisson distribution with mean 90 per hour. Average time for passing through the gate is 38 seconds. Drivers complain of the longwaiting time. Authorities are willing to decrease the passing time through the gate to 30seconds by introducing new automatic devices. This can be justified only if under the oldsystem the number of waiting cars exceeds 5. In addition, the percentage of the gate's idletime under the new system should not exceed 10%. Can the new device be justified?