Explain whether the addition of gallium arsenide in trace amounts to germanium, would produce a $n$-type semiconductor.

One way to gain a physical understanding of b in the van der Waals equation is to calculate the “excluded volume.” Assume that the distance of closest approach between two similar atoms is the sum of their radii (2r). (a) Calculate the volume around each atom into which the center of another atom cannot penetrate. (b) From your result in (a), calculate the excluded volume for 1 mole of the atoms, which is the constant b. How does this volume compare with the sum of the volumes of 1 mole of the atoms?

How are a solid’s unit cell and crystal structure related?

Cesium chloride has the crystal structure shown in Figure 15.30. The length of a side of a unit cell is determined by X-ray diffraction to be $412.1 \mathrm{pm}$. What is the density of cesium chloride?

Compare the temperature dependence of the conductivity for metals and intrinsic semiconductors. Briefly explain the difference in behavior.

A small town has four police cars. If a radio dispatcher receives a call, depending on the nature of the situation, no cars, one car, two cars, three cars, or all four cars can be sent. How many options does the dispatcher have for sending the police cars to the scene of the caller?

The Gotham City police have just received three calls for police. Five cars are available. The distance (in city blocks) of each car from each call is given in Table 69. Gotham City wants to minimize the total distance cars must travel to respond to the three police calls. Use the Hungarian method to determine which car should respond to which call. TABLE 69:

$$\begin{matrix} \text{Car} & \text{Distance (Blocks)}\\ \text{ } & \text{Call 1} & \text{Call 2} & \text{Call 3}\\ \text{1} & \text{10} & \text{11} & \text{18}\\ \text{2} & \text{6} & \text{7} & \text{7}\\ \text{3} & \text{7} & \text{8} & \text{5}\\ \text{4} & \text{5} & \text{6} & \text{4}\\ \text{5} & \text{9} & \text{4} & \text{7}\\ \end{matrix}$$

Fun-in-the-Sun Tanning Lotion Company manufactures suntan lotion made from organic materials. During its first year of operations, it purchased raw materials costing $78,200, of which it used$56,300 in manufacturing suntan lotions. It incurred manufacturing labor costs of $36,100 and manufacturing overhead costs of$26,800 during the year. Inventories taken at the end of the year revealed unfinished suntan lotions costing $12,700 and finished suntan lotions costing$28,500. Compute the amount of cost of goods sold for the year.

Michael Roberts is a cost accountant and business analyst for Darby Design Company (DDC), which manufactures expensive brass doorknobs. DDC uses two direct cost categories: direct materials and direct manufacturing labor. Roberts feels that manufacturing overhead is most closely related to material usage. Therefore, DDC allocates manufacturing overhead to production based upon pounds of materials used.

At the beginning of 2014, DDC budgeted annual production of 410,000 doorknobs and adopted the following standards for each doorknob:

$$\begin{array}{lcr} & \textbf { Input } & \textbf { Cost/Doorknob } \\ \hline \text { Direct materials (brass) } & 0.3 \mathrm{lb} . @ \$ 9 / \mathrm{lb} . & \$~~2.70 \\ \text { Direct manufacturing labor } & 1.2 \text { hours @ } \$ 16 / \mathrm{hour} & 19.20 \\ \text { Manufacturing overhead: } & & \\ \quad \text { Variable } & \$ 4 / \mathrm{lb} . \times 0.3 \mathrm{lb} . & 1.20 \\ \quad \text { Fixed } & \$ 14 / \mathrm{lb} . \times 0.3 \mathrm{lb} . & \underline{~~~~4.20}\\ \text{Standard cost per doorknob}&&\underline{\underline{\$27.30}} \end{array}$$

Actual results for April 2014 were as follows:

1. For the month of April, compute the following variances, indicating whether each is favorable (F) or unfavorable (U):

a. Direct materials price variance (based on purchases)

b. Direct materials efficiency variance

c. Direct manufacturing labor price variance

d. Direct manufacturing labor efficiency variance

e. Variable manufacturing overhead spending variance

f. Variable manufacturing overhead efficiency variance

g. Production-volume variance

h. Fixed manufacturing overhead spending variance

2. Can Roberts use any of the variances to help explain any of the other variances? Give examples.

The Schuyler Corporation manufactures lamps. It has set up the following standards per finished unit for direct materials and direct manufacturing labor: Assume that there was no beginning inventory of either direct materials or finished units. During the month, materials purchased amounted to 100,000 lb., at a total cost of $465,000. Input price variances are isolated upon purchase. Input-efficiency variances are isolated at the time of usage. Required: 1. Compute the January 2017 price and efficiency variances of direct materials and direct manufacturing labor. 2. Prepare journal entries to record the variances in requirement 1. 3. Comment on the January 2017 price and efficiency variances of Schuyler Corporation. 4. Why might Schuyler calculate direct materials price variances and direct materials efficiency variances with reference to different points in time?$

$$\begin{matrix} \text{Direct materials: 10 lb. at \$ 4.50 per lb.} & \text{\$ 45.00}\\ \text{Direct manufacturing labor: 0.5 hour at \$30 per hour} & \text{15.00}\\ \end{matrix}$$

$$The number of finished units budgeted for January 2017 was 10,000; 9.850 units were actually produced. Actual results in January 2017 were as follows:$$

$$\begin{matrix} \text{Direct materials: 98.055 lb. used}\\ \text{Direct manufacturing labor: 4.900 hours} & \text{\$ 154.350}\\ \end{matrix}$$

$

Doug Stevens, the controller of Nexgen, Inc., has asked his assistant, Gayle Sayres, for suggestions as to how the company can improve its reported financial performance for the year. The company is in the last quarter of the year and projections to the end of the year show the company will have a net loss of about $400,000 before tax.

"My suggestion," said Sayres, "is that we sell 1,000 of the 200,000 common shares of Heflin Company that we own. The 200,000 shares give us a 20% ownership of Heflin, and we have been using the equity method to account for this investment. We have owned this stock a long time and the current market value of the 200,000 shares is about$750,000 above our book value for the stock."

"That sale will only generate a gain of about $3,750," replied Stevens. "The rest of the story," continued Sayres, "is that once we sell the 1,000 shares, we will own less than 20% of Heflin. We can then reclassify the remaining 199,000 shares from the influential category to the passive equity/fair value category. Then we value the stocks at their current fair value, including the rest of the$750,000 gain in this year's income statement, and finish the year with a healthy net income."

"But," responded Stevens, "we aren't going to sell all the Heflin stock; 1,000 shares maybe, but certainly not anymore. We own that stock because they are a long-term supplier of ours.

Indeed, we even have representation on their board of directors. The 199,000 shares do not belong in the passive category."

Sayres rolled her eyes and continued, "The classification of an investment as passive or not depends on management's intent. This year-end we claim it was our intent not to exert influence over Heflin. Next year we change our minds and take the stock out of the trading category. Generally accepted accounting principles can't legislate management intent, nor can our outside auditors read our minds. Besides, why shouldn't we take advantage of the flexibility in GAAP to avoid reporting a net loss for this year?"

REQUIRED b. Is it ethical for Doug Stevens to implement the recommendation of Gayle Sayres?

Skulas, Inc., manufactures and sells snowboards. Skulas manufactures a single model, the Pipex. In late 2017, Skulas’s management accountant gathered the following data to prepare budgets for January 2018: Skulas’s CEO expects to sell 2,900 snowboards during January 2018 at an estimated retail price of $650 per board. Further, the CEO expects 2018 beginning inventory of 500 snowboards and would like to end January 2018 with 200 snowboards in stock. Variable manufacturing overhead is$7 per direct manufacturing labor-hour. There are also $81,000 in fixed manufacturing overhead costs budgeted for January 2018. Skulas combines both variable and fixed manufacturing overhead into a single rate based on direct manufacturing labor-hours. Variable marketing costs are allocated at the rate of$250 per sales visit. The marketing plan calls for 38 sales visits during January 2018. Finally, there are $35,000 in fixed nonmanufacturing costs budgeted for January 2018.$

$$\begin{matrix} \text{Materials and Labor Requirements} & \text{ }\\ \text{Direct materials} & \text{ }\\ \text{Wood} & \text{9 board feet (b.f.) per snowboard}\\ \text{Fiberglass} & \text{10 yards per snowboard}\\ \text{Direct manufacturing labor} & \text{5 hours per snowboard}\\ \end{matrix}$$

$$\begin{matrix} \text{ } & \text{Direct Materials Inventories}\\ \text{ } & \text{Beginning Inventory 1/1/2018} & \text{Ending Inventory 1/31/2018}\\ \text{Wood} & \text{2.040 b.f.} & \text{1.540 b.f.}\\ \text{Fiberglass} & \text{1.040 yards} & \text{2.040 yards}\\ \end{matrix}$$

$$Other data include:$$

$$\begin{matrix} \text{ } & \text{2017 Unit Price} & \text{2018 Unit Price}\\ \text{Wood} & \text{\$ 32.00 per b.f.} & \text{\$ 34.00 per b.f.}\\ \text{Fiberglass} & \text{\$ 8.00 per yard} & \text{\$ 9.00 per yard}\\ \text{Direct manufacturing labor } & \text{\$ 28.00 per hour} & \text{\$ 29.00 per hour}\\ \end{matrix}$$

$The inventoriable unit cost for ending finished-goods inventory on December 31, 2016, is$374.80. Assume Skulas used a FiFO inventory method for both direct materials and finished goods. Ignore work in process in your calculations. 1. Prepare the January 2018 revenues budget (in dollars). 2. Prepare the January 2018 production budget (in units). 3. Prepare the direct material usage and purchases budgets for January 2018. 4. Prepare a direct manufacturing labor costs budget for January 2018. 5. Prepare a manufacturing overhead costs budget for January 2018. 6. What is the budgeted manufacturing overhead rate for January 2018? 7. What is the budgeted manufacturing overhead cost per output unit in January 2018? 8. Calculate the cost of a snowboard manufactured in January 2018. 9. Prepare an ending inventory budget for both direct materials and finished goods for January 2018. 10. Prepare a cost of goods sold budget for January 2018. 11. Prepare the budgeted income statement for Skulas, Inc., for January 2018. 12. What questions might the CEO ask the management team when reviewing the budget? Should the CEO set stretch targets? Explain briefly. 13. How does preparing the budget help Skulas's management team better manage the company?

Explain whether the addition of arsenic in trace amounts to germanium, would produce a $n$-type semiconductor.

Show all your work. Indicate clearly the methods you use. In a recent poll, randomly selected New York State residents at various fast-food restaurants were asked if they supported or opposed a "fat tax" on nondiet sugared soda. Thirty-one percent said that they were in favor of such a tax and 66% were opposed. But when asked if they would support such a tax if the money raised were used to fund health care given the high incidence of obesity in the United States, 48% said that they were in favor and 49% were opposed. In this situation, explain how bias may have been introduced based on the way the sample was taken and suggest a way that the sample could have been obtained in order to avoid this bias.