During the last few years we have seen a rise in the production of natural gas in the united states. this lead to a decline in the price of natural gas. if we assume that the price of oil remained roughly the same, this also lead to a reduction in the ratio of the price of natural gas to the price of oil. this resulted in a substitution from oil to natural gas in some production processes. which of the following statements is incorrect in describing this scenario (assume that all else is held constant):
a. the demand for oil changed
b. the quantity demanded of oil decreased
c. the quantity demanded of natural gas increased
d. the demand for oil decreased

Sales at a fast-food restaurant average $6,000 per day. the restaurant decided to introduce an advertising campaign to increase daily sales. to determine the effectiveness of the advertising campaign, a sample of 49 days of sales were taken. they found that the average daily sales were $6,300 per day. from past history, the restaurant knew that its population standard deviation is about $1,000. if the level of significance is 0.01, have sales increased as a result of the advertising campaign? multiple choicea)fail to reject the null hypothesis.b)reject the null hypothesis and conclude the mean is higher than $6,000 per day.c)reject the null hypothesis and conclude the mean is lower than $6,000 per day.d)reject the null hypothesis and conclude that the mean is equal to $6,000 per day.expert answer

Thomas kratzer is the purchasing manager for the headquarters of a large insurance company chain with a central inventory operation. thomas's fastest-moving inventory item has a demand of 6,000 units per year. the cost of each unit is $100, and the inventory carrying cost is $10 per unit per year. the average ordering cost is $30 per order. it takes about 5 days for an order to arrive, and the demand for 1 week is 120 units. (this is a corporate operation, and the are 250 working days per year.)a) what is the eoq? b) what is the average inventory if the eoq is used? c) what is the optimal number of orders per year? d) what is the optimal number of days in between any two orders? e) what is the annual cost of ordering and holding inventory? f) what is the total annual inventory cost, including cost of the 6,000 units?

Which of the following statements about revision is most accurate? (a) you must compose first drafts quickly (sprint writing) and return later for editing. (b) careful writers always revise as they write. (c) revision is required for only long and complex business documents. (d) some business writers prefer to compose first drafts quickly and revise later; others prefer to revise as they go.