Ammonia In a piston/cylinder arrangement is at 700 kPa and 80$^{\circ} \mathrm{C}$. It is now cooled at constant pressure to saturated vapor (state 2), at which point the piston is locked with a pin. The cooling continues to −10$^{\circ} \mathrm{C}$ (state 3). Show the processes 1 to 2 and 2 to 3 on both a P–v and a T–v diagram.

Many drugs decompose in blood by a first-order process.
(e) Calculate $E_a$ for decomposition of the antibiotic in part (d).

In a poll conducted by the Pew Research Center in a certain year, 2000 adults ages 18 years old and older were asked how frequently they are in touch with their parents by phone. The results of the poll are as follows:

If a person who participated in the poll is selected at random, what is the probability that the person said he or she kept in touch with his or her parents:

a. Once a week?

b. At least once a week?

What are valence electrons? Where are they located in an atom? Why are they important?

A shaft with a solid, circular cross section consisting of two segments is shown in part a of the figure. The left-hand segment has a diameter of $80 \mathrm{~mm}$ and length of $1.2 \mathrm{~m}$; the right-hand segment has a diameter of $60 \mathrm{~mm}$ and length of $0.9 \mathrm{~m}$.

Shown in part b of the figure is a hollow shaft made of the same material and having the same length. The thickness $t$ of the hollow shaft is d/l0, where $d$ is the outer diameter. Both shafts are subjeeted to the same torque. (a) If the hollow shaft is to have the same torsional stiffness as the solid shaft, what should be its outer diameter $d$ ? (b) If torque $T$ is applied at either end of both shafts and the bollow shaft is to have the same maximum shear stress as the solid shaft, what should be its outer diamteter $d$ ?

MBank hired El Paso Recovery Services to repossess the Pontiac Trans-Am owned by Sanchez because she was late on her loan payments. The repossessor went to Sanchez’s home with a tow truck and tried to hook the car to the tow truck. Sanchez, who was cutting her grass at the time, asked what they were doing. The repossessors didn’t respond. Sanchez then locked herself in the car to try to stall them until the police arrived. The repossessor finally towed the Trans Am on a high-speed trip, with Sanchez inside, to a repossession lot where they left the car in a fenced and locked yard. Police later rescued Sanchez. She sued MBank. Will she recover? (MBank of El Paso v. Sanchez, 836 S.W.2d 151, Tex.)

A composite shaft consists of a solid steel ( $G=80$ GPa) core with an outside diameter of $40 \mathrm{~mm}$ covered by a brass ( $G=39\ \mathrm{GPa}$ ) tube with an inside diameter of $40 \mathrm{~mm}$ and a wall thickness of $20 \mathrm{~mm}$, which is in turn covered by an aluminum alloy ( $G=28\ \mathrm{GPa}$ ) sleeve with an inside diameter of $80 \mathrm{~mm}$ and a wall thickness of $10 \mathrm{~mm}$, as shown in given figure. The three materials are bonded so that they act as a unit. Find (a) The maximum shearing stress in each material when the assembly is transmitting a torque of $15\ \mathrm{kN} \cdot \mathrm{m}$. (b) The angle of twist in a $3-\mathrm{m}$ length when the assembly is transmitting a torque of $10 \mathrm{kN} \cdot \mathrm{m}$.

A study was conducted of a diagnostic test (the FAIR test, i.e., hip flexion, adduction, and internal rotation) used to identify people with piriformis syndrome (PS), a pelvic condition that involves malfunction of the piriformis muscle (a deep buttock muscle), which often causes lumbar and buttock pain with sciatica (pain radiating down the leg). The FAIR test is based on nerve-conduction velocity and is expressed as a difference score (nerve-conduction velocity in an aggravating posture minus nerve-conduction velocity in a neutral posture). It is felt that the larger the FAIR test score, the more likely a participant will be to have PS. Data are given in the Data Set PIRIFORM.DAT for 142 participants without $\mathrm{PS}$ (piriform = 1) and 489 participants with PS (piriform = 2) for whom the diagnosis of $\mathrm{PS}$ was based on clinical criteria. The FAIR test value is called MAXCHG and is in milliseconds (ms). A cutoff point of $\geq 1.86 \mathrm{~ms}$ on the FAIR test is proposed to define a positive test.

The criterion of $\geq 1.86 \mathrm{~ms}$ to define a positive test is arbitrary. Using different cutoff points to define positivity, obtain the ROC curve for the FAIR test. What is the area under the ROC curve? What does it mean in this context?

Solve the area of the shaded region.

Compute the response of a spring–mass system modeled by equation $m \ddot{x}(t)+k x(t)=F_{0} \cos \omega t$ to a force of magnitude 23 N, driving frequency of twice the natural frequency, and initial conditions given by $x_0 = 0 m$ and $v_0= 0.2 m/s.$ The mass of the system is 10 kg, the spring stiffness is 1000 N/m, and the mass of the spring is considered and known to be 1 kg. What percent does the natural frequency change if the mass of the spring is not taken into consideration?

Use the Theorem of Pappus to find the volume of the solid of revolution. The solid formed by revolving the region bounded by the graphs of y = 2√x-2, y = 0, and x = 6 about the y-axis.

Carry out the indicated calculation. (3 – 4i)(6 + 2i)

The region between the curve $y=1 /(2 \sqrt{x})$ and the x-axis from x = 1/4 to x = 4 is revolved about the x-axis to generate a solid.

Find the volume of the solid.

$\rule{1cm}{1pt}$ and $\rule{1cm}{1pt}$ drugs are used to relieve anxiety and tension without inducing sleep.