Adesign engineer wants to construct a sample mean chart for controlling the service life of a halogen headlamp his company produces. he knows from numerous previous samples that this service life is normally distributed with a mean of 500 hours and a standard deviation of 20 hours. on three recent production batches, he tested service life on random samples of four headlamps, with these results:
what is the standard deviation of the sampling distribution of sample means for whenever service life is in control?
select one:
a. 10 hours
b. 6.67 hours
c. 11.55 hours
d. 5 hours
e. 20 hours

Selected t-account balances for bloomfield company are shown below as of january 31, which reflect its accounting adjustments. the firm uses a calendar-year accounting period, but prepares monthly accounting adjustments.suppliesjan. 31 bal. 1,800 1,800 jan. 31 bal.supplies expensejan. 31 bal. 1,920 1,148 jan. 31 bal.prepaid insurancejan. 31 bal. 1,148 1,148 jan. 31 bal.insurance expensejan. 31 bal. 164 164 jan. 31 bal.wages payablejan. 31 bal. 1,400 1,400 jan. 31 bal.wages expensejan. 31 bal. 6,400 6,400 jan. 31 bal.truckjan. 31 bal. 17,376 17,376 jan. 31 bal.accumulated depreciation -truckjan. 31 bal. 5,068 5,068 jan. 31 bal.a. if the amount in supplies expense represents the january 31 adjustment for the supplies used in january, and $1,240 worth of supplies were purchased during january, what was the january 1 beginning balance of supplies? $answerb. the amount in the insurance expense account represents the adjustment made at january 31 for january insurance expense. if the original insurance premium was for one year, what was the amount of the premium, and on what date did the insurance policy start? amount of the premium $answerthe policy began on answerjune 1july 1august 1september 1october 1november 1 of the previous year.c. if we assume that no beginning balance existed in either in either wage payable or wage expense on january 1, how much cash was paid as wages during january? $answerd. if the truck has a useful life of four years (or 48 months), what is the monthly amount of depreciation expense, and how many months has bloomfield owned the truck? answermonths

The interaction of individual choices because a type of fish is on the verge of extinction, the government imposes rules that prohibit fishing in the publicly owned spawning grounds. at first owners of fshing bouts complain about this restriction on where they can fish, but soon they notice that the number of adult fish swimming outside the protected area is much higher than it was before. with the restriction, each fishing boat ends up catching more fish than it did before the r which of the following principles of economic interaction best describes this scenario? o there is a tradeoff between equality and efficiency o markets usually lead to efficiency. o when markets do not achieve efficiency,government intervention can improve overall welfare o markets allocate goodseffectively

Gdp has grown in a country at 3% per year for the last 20 years. the labor force has grown at 2% per year and the quantity of physical capital has grown at 4% per year. a 1% increase in average physical capital per worker (other things equal) raises productivity by 0.3%. average education has not changed. how much has growing physical capital per worker contributed to productivity growth in this country? choose the correct answer from the following choices, and then select the submit answer button. answer choices 0.3% 0.6% 3.0% 6.0%