Backhoe loader drive system into their backhoe loaders, allowing these models to go over almost any terrain with little difficulty. Since the backhoe was invented, several companies such as Caterpillar and John Deere have changed the backhoe's back arm to be slightly curved like that of an excavator, which can allow more maneuverability. Backhoe loaders are very common and can be used for a wide variety of tasks: construction, small demolitions, light transportation of building materials, powering building equipment, digging holes/excavation, landscaping, breaking asphalt, and paving roads. Often, the backhoe bucket can also be replaced with powered attachments such as a breaker,
Rear admiral rank; and rear admiral (RADM), a two-star rank. Prior to that, a combination of ranks was used. In Vietnam, the equivalent to rear admiral is the "chuẩn đô đốc" or "đề đốc". Rear admiral Rear admiral is a naval commissioned officer rank above that of a commodore (U.S. equivalent of rear admiral lower half) and captain, and below that of a vice admiral. It is generally regarded as the lowest of the "admiral" ranks, which are also sometimes referred to as "flag officers" or "flag ranks". In many navies it is referred to as a two-star rank (OF-7)/(O-7). It originated