Thames Tunnel The oldest underwater tunnel in the world. (0.4 km) (1825 - 1843). Severn Tunnel One of the oldest underwater tunnels in the world (3.62 km) (1873 - 1886). Chesapeake Bay Bridge Tunnel (23 miles (37 km)), connecting Virginia Beach with the Eastern Shore of Virginia (1960 - 1964).
Business Productivity is the ability of an organization to utilize its available resources in order to produce profitable goods or services as desired by customers or clients. It is the productivity that measures the performance of an organization...
Productivity (ecology) In ecology, productivity or production refers to the rate of generation of biomass in an ecosystem. It is usually expressed in units of mass per unit surface (or volume) per unit time, for instance grams per square metre per day (g mâ2 dâ1). The mass unit may relate to dry matter or to the mass of carbon generated.