Sat scores group 1 1520 1630 1480 1580 1400 1300 1700 1610 1580 1520 sat scores group 2 1510 1480 2100 1800 1300 1250 1400 1430 1390 1520 sat scores group 3 1620 1700 1520 1510 1530 1430 2000 1800 1410 1390 sat scores group 4 1480 1570 1400 1800 1930 2150 1340 1580 1530 1610 the sat scores of 4 groups of 10 students are shown. which group has the greatest range?

The weibull distribution is widely used in statistical problems relating to aging of solid insulating materials subjected to aging and stress. use this distribution as a model for time (in hours) to failure of solid insulating specimens subjected to ac voltage. the values of the parameters depend on the voltage and temperature; suppose α = 2.5 and β = 190. (a) what is the probability that a specimen's lifetime is at most 250? less than 250? more than 300? (round your answers to four decimal places.) at most 250 less than 250 more than 300 (b) what is the probability that a specimen's lifetime is between 100 and 250? (round your answer to four decimal places.) (c) what value is such that exactly 50% of all specimens have lifetimes exceeding that value? (round your answer to three decimal places.) hr