A vehicle is stuck on the railroad tracks as a 430,000 lb locomotive is approaching with a speed of 75 mph. As soon as the problem is detected, the locomotive’s emergency brakes are activated, locking the wheels and causing the locomotive to slide. If the coefficient of kinetic friction between the locomotive and the track is 0.45, what is the minimum distance d at which the brakes must be applied to avoid a collision? What would that distance be if instead of a locomotive, there was a $30 \times 106 lb$ train? Treat the locomotive and the train as particles, assume that the railroad tracks are rectilinear and horizontal, and note that only the locomotive’s brakes are applied.

You are working in the emergency department (ED) of a community hospital when the ambulance arrives with A.N., an $18$-year-old woman who was caught in a house fire. She was sleeping when the fire started and managed to make her way out of the house through thick smoke. The emergency medical system crew initiated humidified oxygen at $15 \mathrm{~L} / \mathrm{min}$ per nonrebreather mask and started a $16$-gauge IV with lactated Ringer's solution. On arrival to the ED, her vital signs are $100/66, 125, 34$, $\mathrm{SaO}_2 93 \%$. An additional $16$-gauge IV is inserted. She appears anxious and in pain.

$$\begin{aligned} &\text { Laboratory Test Values }\\ &\begin{array}{ll} \text { Hgb } & 20 \mathrm{~g} / \mathrm{dL} \\ \text { Hct } & 51 \% \\ \mathrm{~K} & 4.9 \mathrm{mEq} / \mathrm{dL} \\ \mathrm{Na} & 133 \mathrm{mEq} / \mathrm{dL} \\ \mathrm{Cl} & 100 \mathrm{mEq} / \mathrm{dL} \\ \text { Glu } & 159 \mathrm{mg} / \mathrm{dL} \\ \text { BUN } & 28 \mathrm{mg} / \mathrm{dL} \\ \text { Cre } & 1.0 \mathrm{mg} / \mathrm{dL} \end{array} \end{aligned}$$

Interpret A.N.'s laboratory results.

Forty patients were asked how many minutes they had to wait in an emergency department before they were seen by a doctor. The results are below. Construct a frequency distribution table using five classes.
32 40 66 51 28 35 30 45 49 33
37 41 56 43 59 60 32 48 56 55
50 29 44 54 64 65 49 34 39 30
36 34 47 52 43 47 58 31 61 29

Heart failure is due to either natural occurrences (87%) or outside factors (13%). Outside factors are related to induced substances or foreign objects. Natural occurrences are caused by arterial blockage, disease, and infection. Suppose that 20 patients will visit an emergency room with heart failure. Assume that causes of heart failure between individuals are independent. (a) What is the probability that three individuals have conditions caused by outside factors? (b) What is the probability that three or more individuals have conditions caused by outside factors? (c) What are the mean and standard deviation of the number of individuals with conditions caused by outside factors?

An 8-year-old child is being admitted to the hospital from the emergency department with an injury from falling off her bicycle. Which of the following will most help her adjust to the hospital?

1. Explain hospital routines such as mealtimes to her.
2. Use terms such as “honey” and “dear” to show a caring attitude.
3. Explain when her parents can visit and why siblings cannot come to see her.
4. Since she is young, orient her parents to her room and hospital facility.

B.L., 17, had a compression fracture at the C5-C6 after jumping into a river from a bridge and slamming into a submerged rock. Fortunately, she was saved by a companion who had first-aid expertise and worked to limit any collateral damage. B.L. was unable to move her limbs, feel touch, or have reflexes in her limbs when she arrived at the emergency room. Describe why it is impossible to determine the entire amount of lasting damage during this initial time frame.

Suppose an emergency van has a single-tone siren with the pitch of the musical note $\mathrm{G}$. If the van is traveling at $80 \mathrm{mph}$ approaching a standing observer, name the pitch the observer hears (rounded to the nearest tenth) and the musical note closest to that pitch.

Pitch of an Octave of Musical Notes in Hertz $(\mathrm{Hz})$

$$\begin{aligned} &\begin{array}{c|c} \hline Note & Pitch \\ \hline Middle\ C & 261.63 \\ \hline D & 293.66 \\ \hline E & 329.63 \\ \hline F & 349.23 \\ \hline G & 392.00 \\ \hline A & 440.00 \\ \hline B & 493.88 \\ \hline \end{array} \end{aligned}$$

The frequency table summarizes the distribution of time that 140 patients at the emergency room of a small-city hospital waited to receive medical attention during the last month.

$$\begin{array}{lr} \hline \text { Waiting time } & \text { Frequency } \\ \hline \text { Less than } 10 \text { minutes } & 5 \\ \text { At least } 10 \text { but less than } 20 \text { minutes } & 24 \\ \text { At least } 20 \text { but less than } 30 \text { minutes } & 45 \\ \text { At least } 30 \text { but less than } 40 \text { minutes } & 38 \\ \text { At least } 40 \text { but less than } 50 \text { minutes } & 19 \\ \text { At least } 50 \text { but less than } 60 \text { minutes } & 7 \\ \text { At least } 60 \text { but less than } 70 \text { minutes } & 2 \\ \hline \end{array}$$

Which of the following represents possible values for the median and IQR of waiting times for the emergency room last month? (a) median = 27 minutes and IQR = 15 minutes (b) median = 28 minutes and IQR = 25 minutes (c) median = 31 minutes and IQR = 35 minutes (d) median = 35 minutes and IQR = 45 minutes (e) median = 45 minutes and IQR = 55 minutes

B.L., 17, had a compression fracture at the C5-C6 after jumping into a river from a bridge and slamming into a submerged rock. Fortunately, she was saved by a companion who had first-aid expertise and worked to limit any collateral damage. B.L. was unable to move her limbs, feel touch, or have reflexes in her limbs when she arrived at the emergency room. Describe the causes and ways in which B.L.'s ability to breathe may be hampered at any time.

Assume that people and businesses have reasonable expectations. Explain how the events listed below will affect aggregate output and the price level. a. The Fed reduces the required reserve ratio unexpectedly. b. Congress passes a tax-cut bill that takes effect in a year and lasts ten years. c. The Fed announces a reduction in the money supply. d. OPEC abruptly reduces oil production by half. e. The government passes an unannounced emergency defence spending bill, authorising a $500 billion increase in funding immediately.

Define Type I and Type II error for each scenario, and identify the cost(s) of each type of error.

Approaching O'Hare for landing, a British Air flight from London has been in a holding pattern for $45$ minutes due to bad weather. Landing is expected within $15$ minutes. The flight crew could declare an emergency and land immediately, but an FAA investigation would be launched and other flights might be endangered. The null hypothesis is that there is enough fuel to stay aloft for $15$ more minutes.

Desert Samaritan Hospital, in Mesa, Arizona, keeps records of emergency room traffic. Those records reveal that the times between arriving patients have a special type of reverse-J-shaped distribution called an exponential distribution. The records also show that the mean time between arriving patients is 8.7 minutes. a. Simulate four random samples of 75 interarrival times each. b. Perform a correlation test for normality on each sample in part (a). Use $\alpha=0.05$. c. Are the conclusions in part (b) what you expected? Explain your answer.

Walking to her car after her 65th birthday party, Mrs. Schultz tripped on ice and fell forward on her outstretched palms. When she arrived at the emergency room, her right wrist and hand were bent like a fork. Dr. Jefferson felt that the styloid process of her radius was outside of the anatomical snuff box and slightly proximal to the styloid process of the ulna. When he checked her elbow, he found that the olecranon lay 2 cm proximal to the two epicondyles of the right humerus. Explain all these observations, and describe what had happened to Mrs.Schultz’s limb.

An emergency cell phone charger requires you to turn a small crank in order to create the energy needed to recharge the phone’s battery. If you turn the crank 120 times per minute, the total number r of revolutions that you turn the crank is given by r = 120t where t is the time (in minutes) spent turning the crank. a. Graph the function and identify its domain and range. b. Identify the domain and range if you stop turning the crank after 4 minutes. Explain how this affects the appearance of the graph.