Driving Safety: Learning to Drive III Questions taken from the PA Drivers' Manual Progress Indicator: Question 2 of 20 2.  Preshift examinations must be conducted within __________ preceding the beginning of any ___________ interval during which any person is scheduled to work or travel underground. Choices: 4 hours, 12-hour 3 hours, 12-hour 3 hours, 8-hour 4 hours, 8-hour