１１、The following appeared in a memo from a vice president of Alta Manufacturing.
　　"During the past year, Alta Manufacturing had thirty percent more on-the-job accidents than nearby Panoply Industries, where the work shifts are one hour shorter than ours. Experts believe that a significant contributing factor in many on-the-job accidents is fatigue and sleep deprivation among workers. Therefore, to reduce the number of on-the-job accidents at Alta and thereby increase productivity, we should shorten each of our three work shifts by one hour so that our employees will get adequate amounts of sleep."