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christine allen

christine a.

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An isotope of a radioactive element has half-life equal to 4 thousand years. Imagine a sample that is so old that most of its radioactive atoms have decayed, leaving just 4 percent of the initial quantity of the isotope remaining. How old is the sample? (Give your answer correct to at least one decimal place.) x thousand years SUBMIT ANSWER

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The majority of eating disorders are first noticed during late childhood or early adolescence. Imagine for a moment that you are a social worker in the school system. Among the schools you are assigned to, one of them has teachers and staff eating with the students. One afternoon, you notice a student who looks to be about 13 years old, sitting by herself in the cafeteria. Although she has been there for about 20 minutes, you notice the food on her tray has been untouched. What, if anything, should you do? Explain your answer.

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[15pts.] Graph the function \(f(x) = \frac{21x-11}{7x+1}\) after making a sign diagram for the first derivative and finding all intercepts (both x and y), relative extreme points (if exists) & asymptotes using limit.

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edwin sutherlands differential association theory is an application of blank to explaining deviance and crime

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Consider the isothermal stirred-tank blending system shown in the following figure. the rate of mass accumulation is given by the following equation: ho V(dx)/(dt)=w_(1)x_(1)+w_(2)x_(2)-wx At the equilibrium we have w=w_(1)+w_(2) Let w_(1)=600k(g)/(m)in w_(2)=2k(g)/(m)in ho =900k(g)/(m^(3)) V=2m^(3) Part 1 Transient and steady-state response analyses Derive the transfer function that relates changes in the change in mass flow rate x as a function of x_(1) and x_(2) Assume that x_(1)=x_(2)=u drive the transfer function of the open loop system x(s)/(u)(s) Determine the damping ratio and the undamped natural frequency of the open loop system. Drive the complete analytical expression for the open-loop step response using the obtained transfer function. Evaluate a. Delay time b. Rise time c. Peak time d. Maximum overshoot e. Settling time Steady-State Error Design via Gain a. Plot the step response and check the damping for the open loop poles of the system. b. Comment on the results Stability analysis Assuming that the mass input can be increased by introducing a gain K a. Find the range of gain required to keep the closed-loop system stable. Steady-state error a. Find the steady-state error in terms of gain, K, for step, ramp, and parabolic inputs. Continuous Blending Process Consider the isothermal stirred-tank blending system shown in the following figure. x1 W1 x2 W V IF the rate of mass accumulation is given by the following equation dx oV =W+WXWX at At the equilibrium we have w =W+W2 Let w=600kg/min w=2kg/min p=900 kg/m3 V =2m3 Part I Transient and steady-state response analyses 1. Derive the transfer function that relates changes in the change in mass flow rate x as a function of and 2. Assume that x=x = u drive the transfer function of the open loop system (s)/u(s) 3. Determine the damping ratio and the undamped natural frequency of the open loop system. 4. Drive the complete analytical expression for the open-loop step response using the obtained transfer function. 5.Evaluate a. Delay time b. Rise time c. Peak time d. Maximum overshoot e. Settling time 6. Steady-State Error Design via Gain a. Plot the step response and check the damping for the open loop poles of the system. b. Comment on the results 7. Stability analysis Assuming that the mass input can be increased by introducing a gain K a. Find the range of gain required to keep the closed-loop system stable 8. Steady-state error a.Find the steady-state error in terms of gain, K, for step, ramp, and parabolic inputs.

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A classifier trained on less training data is less likely to overfit. Question 13 options: True False

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The continuous random variable $X$ has probability density function given by: $f(x) = \begin{cases} k(x+2)^2 & -2 \le x \le 0, \ 0 & \text{otherwise}; \end{cases}$ cumulative distribution function denoted by $F(x)$. (a) Clearly show that $k = \frac{3}{8}$. (b) Find the value of $E(X)$. (c) Show that $Var(X) = 0.15$. (d) Find and specify fully $F(x)$. (e) Determine $P(-1 \le x \le 1)$.

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The Drama Club sold $1,345 worth of tickets for their production of Oliver. Adult tickets sold for $6.75 per ticket, while children's tickets sold for $3.50. If there were 245 tickets sold in all, how many adult tickets were sold?

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Problem 6 Measurement of Stefan-Boltzmann's constant The power emitted by a black body is given by: $\dot{Q} = \sigma \cdot A \cdot T^4$, where $\sigma = 5.67 \times 10^{-8} \frac{W}{K^4 m^2}$ 6.1 What are the units of $T$ and $\dot{Q}$? Sketch $\dot{Q}$ as a function of $T$. 6.2 How could one determine the Stefan-Boltzmann constant using a cooking plate? Give an equati- on for it. Means at hand: thermometer, volt/Ampere meter, cooking plate ($U = 230 V$, $P_{max} = 2 kW$). 6.3 What has to be taken care of to get results close to the real value? (surface of the plate, insulation, ...)?

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The production of Job ACE went much better than planned. In fact, there was a fair amount of good, usable material left over. Dorothy, the production manager, pulled $40 of material from inventory, but used just $29 of material, along with $35 of DL and $12 of MOH. Dorothy believes the material should be put back into circulation, as it could be usable on a different job in the future. If the scrap material is put back into inventory, what is the journal entry to record the completion of Job ACE and the reclassification of material if the company uses the production method to account for scrap? (Credit account titles are automatically indented when the amount is entered. Do not indent manually. If no entry is required, select \"No Entry\" for the account titles and enter 0 for the amounts. List all debit entries before credit entries.) Account Titles and Explanation Debit Credit

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