$$\left. \begin{array} { l } { \text { . The interval between patient arrivals in an emergency room } } \\ { \text { is a random variable with exponential density function } p ( t ) = } \\ { 0.125 e ^ { - 0.125 t } ( t \text { in minutes). What is the average time between pa- } } \\ { \text { tient arrivals? What is the probability of two patients arriving within } 3 } \\ { \text { min of each other? } } \end{array} \right.$$

While you are talking with your friend at an expensive restaurant, she quickly stops in midswallow and looks panicked. When you ask what is wrong, she indicates that she can’t speak and runs toward the restroom. What should you do? Suppose that your first aid does not work---what procedure might emergency medical personnel use to help your her?

In a study of patients arriving at a hospital emergency room, the gender of the patients is considered, together with whether the patients are younger or older than 30 years of age, and whether or not the patients are admitted to the hospital. It is found that $45\%$ of the patients are male, $30\%$ of the patients are younger than 30 years of age, $15\%$ of the patients are females older than 30 years of age who are admitted to the hospital, and $21\%$ of the patients are females younger than 30 years of age. What proportion of the patients are females older than 30 years of age who are not admitted to the hospital?

T.W. is a 22-year-old man who fell SO feet from a chairlift while skiing and landed on hard-packed snow. He is now at the emergency department (ED) with a suspected TS-T6 fracture with paraplegia.
Insert Foley catheter
ECG monitoring
Immobilize the cervical spine
Oxygen at 4 L per nasal cannula
Initiate two large bore IVs
Neurologic assessment every hour
Apply warming blankets as needed
What other interventions would likely be done by the ED nurse?

Potassium superoxide, $KO_2$, is employed in a self-contained breathing apparatus used by emergency personnel as a source of oxygen. The reaction is\

$4KO_2(s) + 2H_2O(l) \longrightarrow 4KOH(s) + 3O_2(g)$\

Say a self-contained breathing apparatus is charged with 750 g $KO_2$ and then is used to produce 195 g of oxygen. Was all of the $KO_2$ consumed in this reaction? If the $KO_2$ wasn’t all consumed, how much is left over and what mass of additional $O_2$ could be produced?

J.R. is a $28$-year-old man who was doing home repairs. He fell from the top of a $6$-foot stepladder, striking his head on a large rock. He experienced a momentary loss of consciousness. By the time his neighbor got to him, he was conscious but bleeding profusely from a laceration over the right temporal area. The neighbor drove him to the emergency department of your hospital. As the nurse, you immediately apply a cervical collar, lay him on a stretcher, and take J.R. to a treatment room.

Differentiate between a primary and secondary head injury.

The frequency distribution shows the number of medical tests conducted on 30 randomly selected emergency room patients.

If a patient is selected at random, find these probabilities:

a. The patient had exactly 3 tests done. b. The patient had at most 2 tests done. c. The patient has 1 or 2 tests done. d. The patient had fewer than 3 tests done. e. The patient had at least 3 tests done.

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.

A plane leaves Seattle, flies $85 \mathrm{mi}$ at $22^{\circ}$ north of east, and then changes direction to $48^{\circ}$ south of east. After flying at $115 \mathrm{mi}$ in this new direction, the pilot must make an emergency landing on a field. The Seattle airport facility dispatches a rescue crew.
($a$) In what direction and how far should the crew fly to go directly to the field? Use components to solve this problem.
($b$) Check the reasonableness of your answer with a careful graphical sum.

(a) Recall Which amendment guaranteed African Americans the right to vote: the Thirteenth, Fourteenth, or Fifteenth?

(b) Apply Information How did each of these three amendments help to expand democracy?

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 necessity for caution while handling a person who may have had a spinal cord injury.

You are on duty in the emergency department (ED) when a "code blue" is called. As the code nurse, you grab the crash cart and run to the code, which is in the employee lounge of the operating room. On the couch, you find a nurse, Z.H., unconscious, dusky, and barely breathing
Z.H.'s respiratory rate is 8 and shallow. The respiratory therapist intubates her and continues to ventilate her manually. You attach ECG leads to her chest and find the results shown in the figure. What is your interpretation of Z.H.'s rhythm?

(Use Excel) Color coding is often used in manufacturing operations to display production status or to identify/prioritize materials. For example, suppose "green" status indicates that an assembly line is operating normally, "yellow" indicates it is down waiting on personnel for set up or repair, "blue" indicates it is down waiting on materials to be delivered, and "red" indicates an emergency condition. Management has set realistic goals whereby the assembly line should be operating normally 80% of the time, waiting on personnel 9% of the time, waiting on materials $9 \%$ of the time, and in an emergency condition 2% of the time. Based on $250$ recent status records, the status was green $185$ times, yellow $24$ times, blue $32$ times, and red $9$ times.

a. State the appropriate null and alternative hypotheses to test if the proportions of assembly line statuses differ from the goals set by management.

b. Calculate the value of the test statistic.

c. Use Excel's CHISQ.DIST.RT function to calculate the $p$-value.

d. Are management's goals being met at $\alpha=0.05$ ? Will your conclusion change at $\alpha=0.01$ ?

The flywheel of an old steam engine is a solid homogeneous metal disk of mass $M=120 \mathrm{~kg}$ and radius $R=80.0 \mathrm{~cm}$. The engine rotates the wheel at 500 . rpm. In an emergency, to bring the engine to a stop, the flywheel is disengaged from the engine and a brake pad is applied at the edge to provide a radially inward force $F=100$. N. If the coefficient of kinetic friction between the pad and the flywheel is $\mu_{\mathrm{k}}=0.200$, how many revolutions does the flywheel make before coming to rest? How long does it take for the flywheel to come to rest? Calculate the work done by the torque during this time.