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Research studies include both a research hypothesis, which states what the researcher thinks will be found, and a null hypothesis is true? calculate the molar concentration of h3o ions and the ph of the following solutions: (a) 25.0 cm3 of 0.144 m hcl(aq) was added to 25.0 cm3 of 0.125 m naoh(aq), (b) 25.0 cm3 of 0.15 m hcl(aq) was added to 35.0 cm3 of 0.15 m koh(aq), and (c) 21.2 cm3 of 0.22 m hno3(aq) was added to 10.0 cm3 of 0.30 m naoh(aq). Endogeneity I Consider the simple regression model: y = Bo + Bir + , and let z be an instrumental variable for r. (a) Derive an IV estimator in this case and comment on its i) unbiasedness and ii) consistency. How can you cxpress an estimator if z is a binary variable? 1 (b) Express the probability limit of the IV estimator in terms of population corre- lations between z and (Corr (z, )) and z and 2 (Corr (2, 2)). Compare it with the OLS estimator's probability limit. On the asymptotic bias grounds, under what conditions is IV preferred to OLS? (c) Let the regression of x onto z have R2 = 0.05 and n = 100. Is z a strong instrument? (d) Let you now have access to two instrumental variables, namely z and zz. The value of the J-statistic is J = 18.2. Does this imply that E ( 21,22) +0? Alan was recently paid by Tracy for work Alan performed at Tracy's house. Tracy writes a check to Alan for $1,000. Before cashing the check at his bank, Alan adds a zero to make the check read $10,000 instead of $1,000. Based upon these facts alone, Alan may have committed the crime of 6. Maya and Karen were working together on arational equation. Their problem wasX + 112= 4-X-3X-2X-3Maya solved the problem and got the solution{-3,5} and Karen's solutions wereWhich of the friends is correct?A. Maya is correct. Karen incorrectlycombined like terms.B.Karen is correct. Maya incorrectlycombined like terms.C. Neither girl is correct.D. Both girls are correct and all thoseanswers are solutions. What are the key differences in the organization of source-oriented records, problem-oriented records (PORs), electronic documentation systems, and CBE systems? help asap!!!!!!!!!!!!! Who wrote African Americans in Film and Television Entertainment? what storyboarding technique uses a combination of two techniques, and which techniques does it combine? the nurse is reviewing calcium regulation. which physiological response should the nurse expect when the thyroid gland releases calcitonin? Which part of plate tectonics do the pieces of paper represent? Convection currents heat from Earth's core _____plate boundariesWhich part of plate tectonics does the movement of food coloring represent? _____heat from Earth's coreEarth's plates plate boundariesWhich part of plate tectonics does the candle represent?Convection currentsEarth's plates plate boundaries g how much can the unit cost of making model 1 slip rings increase before it becomes more economical to buy some of model 1 slip rings? explain a hair stylist makes $44 each day that she works and makes approximately $16 in tips for each hair cut that she gives. if she wants to make at least $108 in one day, at least how many hair cuts does she need to give? Requirement to Playback more than 12 Streams simultaneously may require... 05-004 - Definition of data analysis fairness The probability that a person has immunity to a particular disease is 0.6. Find the mean for the random variable X, the number who have immunity in samples of size 26. The iframe tag can be used for loading malicious code (often in the form of JavaScript applet) onto an otherwise trusted page.- True- False hurry i need help with this i dont know what to write When moving from left to right across a period, the outer electrons feel a ____ attraction towards the nucleus and the atomic radius ____. (1 point) Find the total mass of the region bounded by thecurves y=2/x, x=1, x=4, and the x-axis. All lengths are incentimeters, and the density of the region is (x)=x^1/3grams/cm^2.