Clean Water Rule coverage would produce a 2:1 ratio of benefits to costs in implementation after the final rule. Implementation of the rule will discern any implications for environmental justice communities, though it is clear that "meaningful involvement from minority, low-income, and indigenous populations, as well as other stakeholders, has been a cornerstone of development of the final rule." Specific details that have been clarified by the rule are outlined below. A tributary, or upstream water, must show physical features of flowing water – a bed, bank, and ordinary high water mark – to warrant protection. The rule provides protection for headwaters that
Slide rule route segments. Slide rules are still commonly used in aviation, particularly for smaller planes. They are being replaced only by integrated, special purpose and expensive flight computers, and not general-purpose calculators. The E6B circular slide rule used by pilots has been in continuous production and remains available in a variety of models. Some wrist watches designed for aviation use still feature slide rule scales to permit quick calculations. The Citizen Skyhawk AT is a notable example. Even today, some people prefer a slide rule over an electronic calculator as a practical computing device. Others keep their old slide rules out