The Prehistory of Jazz. The Africanization of American Music. An elderly black man sits astride a large cylindrical drum. Using his fingers and the edge of his hand, he jabs repeatedly at the drum head--which is around a foot in diameter and probably made from an animal skin--evoking a throbbing pulsation with rapid, sharp strokes.
nope, efficiency o fa machine cannot be greater than 100%...theoretically it shows sometime that efficiency of a machine can be 100%, but practically it cannot be possible as â¦ there is some loss of energy is always involved in different ways. Answer   In order for a machine to be 100% efficient, the amount of energy going into it has to be precisely equal to the energy the machine is putting out-with nothing lost.
U.S. labor costs could shrink by 22 percent if machines complete only 25 percent of the tasks they're capable of performing. By Andrew Soergel, Economy Reporter | Feb. 10, 2015, at 12:05 p.m. Robots Could Cut Labor Costs 16 Percent by 2025. Robots install rivets on a 2015 Ford F-150 truck on Nov. 11, 2014, in Dearborn, Mich.