The following observations are on stopping distance (ft) of a particular truck at 20 mph under specified experimental conditions (“Experimental Measurement of the Stopping Performance of a Tractor-Semitrailer from Multiple Speeds,” NHTSA, DOT HS 811 488, June 2011):

$$\begin{matrix} \text{32.1} & \text{30.6} & \text{31.4} & \text{30.4} & \text{31.0} & \text{31.9}\\ \end{matrix}$$

The cited report states that under these conditions, the maximum allowable stopping distance is 30. A normal probability plot validates the assumption that stopping distance is normally distributed. Does the data suggest that true average stopping distance exceeds this maximum value? Test the appropriate hypotheses using $\alpha=.01$.

A two-stage compression refrigeration system operates with refrigerant-134a between the pressure limits of 1.4 and 0.10 MPa. The refrigerant leaves the condenser as a saturated liquid and is throttled to a flash chamber operating at 0.4 MPa. The refrigerant leaving the low-pressure compressor at 0.4 MPa is also routed to the flash chamber. The vapor in the flash chamber is then compressed to the condenser pressure by the high-pressure compressor, and the liquid is throttled to the evaporator pressure. Assuming the refrigerant leaves the evaporator as saturated vapor and both compressors are isentropic, determine (a) the fraction of the refrigerant that evaporates as it is throttled to the flash chamber, (b) the rate of heat removed from the refrigerated space for a mass flow rate of 0.25 kg/s through the condenser, and (c) the coefficient of performance.

Refer to The Sport Journal (Winter 2004) study on the effectiveness of a speed-training program for football players. The decreases in 40-yard sprint times (time after training minus time before training) for 38 players are saved in the SPRINT file. An athlete's sprint performance will be classified as "improved" if the "after" time is less than the "before" time, and classified as "Not Improved" if otherwise. a. Find an estimate for the true proportion of all high school athletes who attain improved sprint times after participating in the speed-training program. b. Convert the estimate, part a, into a 95% confidence interval. Give a practical interpretation of the result. c. How many high school athletes should be sampled to estimate the true proportion to within .03 with 95% confidence?

Assume the role of assistant buyer for a costume jewelry store. You are ordering a shipment of earrings in five styles from a supplier. The cost of the earrings is $\$ 1.50$ per pair. You know that if you set too low a selling price the earrings will not sell well. The buyer (judge) has asked you to prepare a pricing strategy for the earrings. Among the decisions you must make is whether to price all the styles at one price point or to price the different styles at separate price points.

Present your pricing strategy to your supervisor (judge).

You will be evaluated on how well you meet the following performance indicator:

Use psychological pricing to adjust base prices

Most baseball hitters perform differently against right-handed and left-handed pitching. Consider two players, Joe and Moe, both of whom bat right-handed. The table below records their performance against right-handed and left-handed pitchers.

Make a separate two-way table of player versus outcome for each kind of pitcher. From these tables, find the batting averages of Joe and Moe against right-handed pitching. Who does better? Do the same for left-handed pitching. Who does better?

Assume the role of assistant buyer for a costume jewelry store. You are ordering a shipment of earrings in five styles from a supplier. The cost of the earrings is $\$ 1.50$ per pair. You know that if you set too low a selling price the earrings will not sell well. The buyer (judge) has asked you to prepare a pricing strategy for the earrings. Among the decisions you must make is whether to price all the styles at one price point or to price the different styles at separate price points.

Present your pricing strategy to your supervisor (judge).

You will be evaluated on how well you meet the following performance indicator:

Select promotional pricing strategies used to adjust base prices

Two basketball players on a school team are working hard on consistency of their performance. In particular, they are hoping to bring down the variance of their scores. The coach believes that the players are not equally consistent in their games. Over a 10-game period, the scores of these two players are shown in the accompanying table. Assume that the two samples are drawn independently from normally distributed populations.

$$\begin{array}{|c|c|c|c|c|c|c|c|c|c|c|} \hline \text { Player 1 } & 13 & 15 & 12 & 18 & 14 & 15 & 11 & 13 & 11 & 16 \\ \hline \text { Player 2 } & 11 & 21 & 18 & 9 & 20 & 11 & 13 & 11 & 19 & 8 \\ \hline \end{array}$$

Is the number of years of competitive running experience related to a runner's distance running performance? The data on nine runners, obtained from the study by Scott Powers and colleagues, are shown in the table:

Runner: 1, 2, 3, 4, 5, 6, 7, 8, 9 Years of Competitive Running: 9, 13, 5, 7, 12, 6, 4, 5, 3 10-Kilometer Finish Time (minutes): 33.15, 33.33, 33.50, 33.55, 33.73, 33.86, 33.90, 34.15, 34.90

a. Calculate the rank correlation coefficient between years of competitive running x and a runner's finish time in the 10-kilometer race. b. Do the data provide evidence to indicate a significant rank correlation between y and x? Test using $\alpha$=.05.

Oil executives frequently compare the performance and efficiency of their company with those of other major oil companies. The following data is taken from Total Oil's $2013$ accounts.

$$\begin{array}{|l|l|l|l|l|l|l|l|} \hline\text{ Credit } & \text{ Creditors } & \text{ Debtors } & \text{ Long-term } & \text{ Inventories } & \text{ Cost of } & \text{ Capital } & \text{ Credit }\\ \text{ sales (\$m)} & \text{ (accounts } & \text{ (accounts } & \text{ loans(\$m)} & \text{ (\$m) } & \text{ sales (\$m) } & \text{ employed } & \text{ purchases } \\ & \text{ payable) } & \text{ receivable) } &&&& \text{ (\$m) } & \text{ (author’s } \\ & \text{ (\$m) } & \text{ (\$m) } &&&&& \text{ estimate)(\$m)} \\ \hline227969 & 30282 & 23422 & 34574 & 22097 & 160849 & 177555 & 160000 \\ \hline \end{array}$$

Calculate the creditor days ratio for Total Oil in $2013$.

We could improve the performance of the waterproofing process discussed in the previous exercise by making an adjustment that moves the center of the process to $\mu=2500 \mathrm{~mm}$, the center of the specifications. We should do this even if the original specifications remain in force, because this will require less sealer and therefore cost less. Suppose that we succeed in moving $\mu$ to 2500 with no change in the process variability $\sigma$, estimated by $s=383.8$. (a) What are $\mathrm{C}^{\wedge} \mathrm{p}$ and $\mathrm{C}^{\wedge} \mathrm{pk}$ with the original specifications? Compare the values with those from part (a) of the previous exercise. (b) What are $\mathrm{C}^{\wedge} \mathrm{p}$ and $\mathrm{C}^{\wedge} \mathrm{pk}$ with the tightened specifications? Again compare with the previous results.

A square cross-section duct $(0.5 \mathrm{~m} \times 0.5 \mathrm{~m} \times 30 \mathrm{~m})$ is used to convey air $\left(\rho=1.1 \mathrm{~kg} / \mathrm{m}^{3}\right)$ into a clean room in an electronics manufacturing facility. The air is supplied by a fan and passes through a filter installed in the duct. The duct friction factor is $f=0.03$, the filter has a loss coefficient of $K=12$, and the clean room is kept at a positive gage pressure of $50 \mathrm{~Pa}$. The fan performance is given by $\Delta p=1020-25 Q-30 Q^{2}$, where $\Delta p$ $\mathrm{(Pa)}$ is the pressure generated by the fan at flow rate $Q\left(\mathrm{~m}^{3} / \mathrm{s}\right)$. Find the flow rate delivered to the room.

Mark Washington, CFA, is an analyst with BIC. One year ago, BIC analysts predicted that the U.S. equity market would most likely experience a slight downturn and suggested delta-hedging the BIC portfolio. As predicted, the U.S. equity markets did indeed experience a downturn of approximately 4% over a 12-month period. However, portfolio performance for BIC was disappointing, lagging its peer group by nearly 10%. Washington has been told to review the options strategy to determine why the hedged portfolio did not perform as expected. Washington considers a put option that has a delta of −.65. If the price of the underlying asset decreases by $6, then what is the best estimate of the change in option price?

Choose a word to replace the italicized word in the sentence. All of the possible choices have similar definitions, but the correct answer will have a connotation that best suits the context and does not render the sentence awkward in tone or content. When choices seem close, look for a clue in the context that makes one choice better than the other.

$$\begin{array}{llll}\text { typical } & \text { crime } & \text { problem } & \text { hackneyed } \\ \text { imperious } & \text { show } & \text { intentions } & \text { machinations } \\ \text { affectation } & \text { failure } & \text { normal } & \end{array}$$

Not wanting to trouble his grandma with his many worries, Luke put on a[n] performance of cheerfulness when he visited her this week.

Better word: ______

To formulate the performance of a multiple-access network, we need a mathematical model. When the number of stations in a network is very large, the Poisson distribution, $p[x] = (e^{−\lambda} \times \lambda^x)/(x!)$, is used. In this formula, p[x] is the probability of generating x number of frames in a period of time and $\lambda$ is the average number of generated frames during the same period of time. Using the Poisson distribution: a. Find the probability that a pure Aloha network generates x number of frames during the vulnerable time. Note that the vulnerable time for this network is two times the frame transmission time (Tfr). b. Find the probability that a slotted Aloha network generates x number of frames during the vulnerable time. Note that the vulnerable time for this network is equal to the frame transmission time (Tfr).