Economic theory works on the premise that there are two types of employment: basic and non-basic. Economic base theory claims that basic employment is the engine of a local economy largely because its ...

Since the first time somebody figured out that they could propel an object out the end of a crudely-fashioned iron tube by igniting a concoction of sulfur, charcoal, and piss, humankind has strived to ...

Type 96A Main Battle Tanks (MBT) attached to the PLA 73rd Group Army fire 125-millimeter guns during live-fire training exercise in East China's Fujian Province on July 4, 2017. Photo: 81.cn The ...

Refractor to reflector, Schmidt-Cassegrain to Maksutov-Cassegrain - this is everything you need to know about the different types of telescopes. When you purchase through links on our site, we may ...