This month, Judy has checked out 20 books from the library, and of them were biographies. Which expression can be used to determine the number of biographies Judy checked out?

Employees of dti, inc. worked 1,600 direct labor hours in january and 1,000 direct labor hours in february. dti expects to use 18,000 direct labor hours during the year, and expects to incur $22,500 of worker’s compensation insurance cost for the year. the cash payment for this cost will be paid in april. how much insurance premium should be allocated to products made in january and february?

Areal estate agent is considering changing her cell phone plan. there are three plans to choose from, all of which involve a monthly service charge of $20. plan a has a cost of $.42 a minute for daytime calls and $.17 a minute for evening calls. plan b has a charge of $.52 a minute for daytime calls and $.15 a minute for evening calls. plan c has a flat rate of $80 with 275 minutes of calls allowed per month and a charge of $.38 per minute beyond that, day or evening.a. determine the total charge under each plan for this case: 150 minutes of day calls and 70 minutes of evening calls in a month. (do not round intermediate calculations. round your answer to 2 decimal places. omit the "$" sign in your response.)c. if the agent will use the service for daytime calls, over what range of call minutes will each plan be optimal? (round each answer to the nearest whole number.include the indifference point itself in each answer.)d. suppose that the agent expects both daytime and evening calls. at what point (i.e., percentage of total call minutes used for daytime calls) would she be indifferent between plans a and b?

Ashop owner uses a reorder point approach to restocking a certain raw material. lead time is six days. usage of the material during lead time is normally distributed with a mean of 42 pounds and a standard deviation of four pounds. when should the raw material be reordered if the acceptable risk of a stockout is 3 percent?