1. The details of weekly output and input for a fabrication process are as follows: output is 400 units, with a standard selling price of $120 per unit. For the week, total labor costs are: 6 workers at 40 hours for the week, are paid $15 per hour. Total material costs for the 400 units are $5,200. Weekly overhead is charged at the rate of 2 times the labor costs. What is the multifactor productivity for the week?

2. A couple planning a vacation needs to choose between four different modes of transportation as shown in the table. Depending on the weather, either excellent or bad, they have estimated their daily comfort expenses. A pessimistic couple would opt for a(n) ________ based on the information presented in the table below.

	Excellent Weather	Bad Weather
Plane	$70	$38
Boat	$22	$90
Automobile	$9	$52
Train	$44	$24

3. Zipco is in serious negotiations to purchase a chunking machine that will enable them to perform their own chunking at $15 per unit. Their marketing team feels that they can sustain an annual volume of 9,000 units. Chunks sell for $20.50 per chunk. What is the maximum fixed cost that Zipco should be willing to bear in order to perform their own chunking?

4. A couple planning a vacation needs to choose between four different modes of transportation as shown in the table. Depending on the weather, either excellent or bad, they have estimated their daily comfort expenses. An optimistic couple would opt for a(n) ________ based on the information presented in the table below.

	Excellent Weather	Bad Weather
Plane	$70	$38
Boat	$22	$90
Automobile	$9	$52
Train	$44	$24

5. A small coffee shop is planning to add a banana nut muffin to its menu. Fixed annual costs are estimated at $6,100 and variable costs are estimated at $3.25 per muffin. The coffee shop wants to break even if 1,625 banana nut muffins are sold per year. What price should they set for the banana nut muffin? round the final answer to a whole number.

6. A poultry farmer is debating whether to acquire Rhode Island Reds or Buff Orpingtons to lay the eggs he wants to sell. The fixed costs for the Buffs would be $60,000 and the variable costs per egg would be $.50 per egg. The Reds would have a fixed cost of $75,000 and a variable cost of $.20 per egg. At what level of egg production would the poultry farmer be indifferent between Rhode Island Reds and Buff Orpingtons?

Use the water quality monitoring data from Heidelberg University (Chapter 2, Exercise 4) to

• plot TP (total phosphorus) against sampling dates to visualize the changes of TP over time and compare the temporal pattern of SRP to that of river discharge (flow). Describe the seasonal patterns in both.

• plot TP against flow, both in the original and log scales to examine the correlation between TP and flow.

Chapter 2, Exercise 4

The Heidelberg University in Tiffin, Ohio, U.S.A., maintains a long-term monitoring program of several Lake Erie tributaries. The water quality and flow data from the Maumee River station near Waterville, Ohio, can be found at http://www.heidelberg.edu/sites/default/files/ dsmith/files/MaumeeData.xlsx.

(a) Convert the date column into R dates.

(b) Summarize flow and total phosphorus by year and by month.

(c) Plot flow and TP over time.