Las notas del curso a tuvieron una media aritmetica de 75 puntos y un varianza de 225 las del curso b tuvieron una media de 70 puntos y una varianza de 196. si en ambos cursos las notas se aumentan en 10% cuales de los dos cursos tienen un coeficiente de variacion mayor despues de arreglar las notas

Afour cylinder four-stroke in-line engine has a stroke of 160mm, connecting rod length of 150mm, a reciprocating mass of 3kg and its firing order is 1-3-4-2. the spacing between cylinders is 100mm. i. show that the engine is in balance with regard to the primary inertia forces and primary 3. a and secondary inertia couples. li determine the out of balance secondary inertia force ii. propose ways of balancing this out of balance force and discuss the challenges that will arise

Air inially occupying a volume of 1 m2 at 100 kpa, 27 c undergoes three internally reversible processes in series. process 1-2 compression to 500 kpa during which pv constant process 2-3 adiabatic expanslon to 100 kpa process 3-1: constant-pressure expansion to 100 kpa (a) calculate the change of entropy for each of the three processes. (b) calculate the heat and work involved in each process. (c) is this cycle a power cycle or refrigeration cycle?

The sum of the normal stresses does not change as the stress state rotates through an angle. a)-trune b)- false