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).
BACKGROUND: The primary mineral in limestone is calcite or calcium carbonate ( CaCO3). When carbon dioxide ( CO2 ) reacts with water, carbonic acid is produced, see BUBBLES IN YOUR. WATER ACTIVITY. When an acid, such as carbonic acid, reacts with limestone, the limestone.