Oxygen masks for producing $\mathrm{O}_2$ in emergency situations contain potassium superoxide $\left(\mathrm{KO}_2\right)$. It reacts according to this equation:

$$4\mathrm{~KO}_2+2\mathrm{~H}_2 \mathrm{O}+4\mathrm{~CO}_2\longrightarrow 4\mathrm{~KHCO}_3+3\mathrm{~O}_2$$

(a) If a person wearing such a mask exhales $0.85 \mathrm{~g}$ of $\mathrm{CO}_2$ every minute, how many moles of $\mathrm{KO}_2$ are consumed in $10.0$ minutes?
(b) How many grams of oxygen are produced in $1.0$ hour?

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.

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.

A recently graduated mechanical engineer wants to build a reserve fund as a safety net to pay his expenses in the unlikely event that an unexpected emergency arises. His aim is to have $45,000 developed over the next 3 years, with the proviso that the amount must have the same purchasing power as$45,000 today. If the expected market rate on investments is 8% per year and inflation is averaging 2% per year, find the annual amount necessary to meet his goal.

Malcolm injured himself after trying to break his fall with outstretched arms. The emergency room physician took one look at his shoulder and saw that Malcolm had a broken clavicle (and no other injury). Describe the position of Malcolm’s shoulder. What part of the clavicle was most likely broken? Malcolm was worried about injury to the main blood vessels to his arm (the subclavian vessels), but he was told such injury was unlikely. Why could the doctor predict this?

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.

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.

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 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.

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.

Identify at least five signs and symptoms of increased ICP.

A patient is evaluated in the emergency department after causing an automobile accident while being under the influence of alcohol. While assessing the patient, which statement would be the most therapeutic?

1. “Why did you drive after you had been drinking?”
2. “We have multiple patients to see tonight as a result of this accident.”
3. “Tell me what happened before, during, and after the automobile accident tonight.”
4. “It will be okay. No one was seriously hurt in the accident.”

Two small liquid-propellant rocket motors are mounted at the tips of a helicopter rotor to augment power under emergency conditions. The diameter of the helicopter rotor is $7 \mathrm{~m}$, and it rotates at $1 \mathrm{rev} / \mathrm{s}$. The air enters at the tip speed of the rotor, and exhaust gases exit at $500 \mathrm{~m} / \mathrm{s}$ with respect to the rocket motor. The intake area of each motor is $20 \mathrm{~cm}^2$, and the air density is $1.2 \mathrm{~kg} / \mathrm{m}^3$. Estimate the power provided by the rocket motors. Ignore the mass rate of flow of fuel in this calculation.

Evaluate the expression to complete the table. "

$$\begin{matrix} & \text{Mammals with the Longest Tails}\\ \text{Mammal} & \text{Expression} & \text{Tail Length}\\ \text{African buffalo} & \mathrm{51 + 6 ^ { 2 } \div 9 - 12} & \text{\_\_\_\_\_}\\ \end{matrix}$$

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