Brand x batteries have a mean life span of 102 hours, with a standard deviation of 6.8 hours. brand y batteries have a mean life span of 100 hours, with a standard deviation of 1.4 hours. complete each of the sentences.

about 68% of brand x’s batteries have a lifespan between and hours. about 68% of brand y’s batteries have a lifespan between and hours. the life span of brand ’s battery is more likely to be consistently close to the mean.

Electronics assembly inc. is a contract manufacturer that assembles consumer electronics for a number of companies. currently, the operations manager is assessing the capacity requirements as input into a bid for a job to assemble cell phones for a major global company. the company would assemble three models of cell phones in the same assembly cell. setup time between the phones is negligible. electronics assembly inc. operates two 8-hour shifts for 275 days per year. cell phone demand forecast (phones/year) processing time (minutes/phone) mars 47,000 19.8 saturn 35,000 20.7 neptune 7,500 16.2 a. calculate total capacity required by line. b. determine the total operating time available. c. calculate the total number of assembly cells. (round up your answer to the next whole number.)

In transportation model analysis, the stepping-stone method is used to: a. obtain an initial feasible solutionb. evaluate empty cells for possible degeneracyc. evaluate empty cells for potential solution improvementsd. identify a dummy origin pointe. balance supply and demand

Russell's study compared gpa of those students who volunteered for academic study skills training and those who did not elect to take the training. he found that those who had the training also had higher gpa. with which validity threat should russell be most concerned?