Aself-contained machine has, as its input, two equal steady streams of a fluid at temperatures t and 47, respectively. the only output is a single high speed jet of the same fluid at temperatures t. the heat capacity per unit mass of the fluid is c (and is independent of the temperature). what is the maximum possible speed of the jet? [hint: the process is irreversible] ст, (a) 4 (b) 4ст (d) ct (с) /2сt