A firm manufactures a commodity at two different factories, Factory X and Factory Y. The total cost (in dollars) of manufacturing depends on the quantities, I and y produced at each factory, respectively, and is
expressed by the joint cost function:
C(x, y) = 4x + xy + 8y2 + 4400
A) If the company's objective is to produce 500 units per month while minimizing the total monthly cost of
production, how many units should be produced at each factory? (Round your answer to whole units, i. e. no
decimal places.)
To minimize costs, the company should produce:
units at Factory X and
units at Factory Y
dollars. (Do not
B) For this combination of units, their minimal costs will be
enter any commas in your answer.)

The survey of study habits and attitudes (ssha) is a psychological test that measures the motivation, attitude toward school, and study habits of students, scores range from 0 to 200. the mean score for u.s. college students is about 115, and the standard deviation is about 30. a teacher who suspects that older students have better attitudes toward school gives the ssha to 55 students who are at least 30 years of age. the mean score is 113.2. assume the population standard deviation is 30 for older students what is the margin of error for a 95% confidence interval for the population mean score for a. older students? b. compute the 95% confidence interval for the population mean score for older students. c. compute the 99% confidence interval for the population mean score for older students. d. compute the 88% confidence interval for the population mean score for older students.