Both these effects reduce the workload of the heart, so beta blockers are of value in treating the symptoms of angina pectoris, the chest pain brought on by narrowing of the coronary arteries that causes inadequate delivery of oxygen-rich blood to the heart muscle.
3 1. The invention and the history of the Dell computer is quite interesting. First of all, it was in 1984 when Michael Dell, a student at the University of Texas at Austin, created the company PC's Limited. He only had a starting capital of $1,000.
We could argue that the first computer was the abacus or its descendant, the slide rule, invented by William Oughtred in 1622.But the first computer resembling today's modern â¦ machines was the Analytical Engine, a device conceived and designed by British mathematician Charles Babbage between 1833 and 1871.e could argue that the first computer was the abacus or its descendant, the slide rule, invented by William Oughtred in 1622.