FTR is a British rapid-transit bus system, currently in operation in Leeds, Luton and Swansea.irst Group has introduced the system, using Wright StreetCar articulated buses in conjunction with infrastructure upgrades by local authorities. The vehicles have been branded as the future of travel, the operators claiming that ftr is textspeak for the word future.
Limestone is a sedimentary rock, composed mainly of skeletal fragments of marine organisms such as coral, forams and molluscs. Its major materials are the minerals calcite and aragonite, which are different crystal forms of calcium carbonate (CaCO3).
Limestone is found in many parts of the world, both on land and in water, including Central America and England. Numerous conditions exist to produce many types of limestone. The skeletons of invertebrate animals make up limestone originating from coral reefs. Algae that live within the reefs secrete calcium carbonate to seal the structures of the organisms together, helping to form the hardened structures.