1.1) (Ch. 7) Explain what a residual is (also known as residual of prediction).
e idea of “least squares” in regression (you need to fully read pp. 200-208 to understand).
3) What does it mean if b = 0?
4) What does it mean when r-squared is 0? What does it mean when r-squared is 1?
5) What is the difference in an unstandardized regression coefficient and the standardized regression coefficient?
6) If a report says test performance was predicted by number of cups of coffee (b = .94), what does the .94 mean? Interpret this. (For every one unit increase in ___,There is an increase in ___ )
7) If F (2,344) = 340.2, p < .001, then what is this saying in general about the regression model? (see p. 217)
8) Why should you be cautious in using unstandardized beta? (p. 218)
9) (Ch. 8) Explain partial correlation in your own words. In your explanation, explain how it is different from zero-order correlation (aka Pearson r).
10) (Ch. 9) What is the F statistic used to determine in multiple regression?
11) What is F when the null hypothesis is true?
12) In Table 9.4, which variable(s) are statistically significant predictors?
13) In Table 9.4, explain what it means if health motivation has b = .36 in terms of predicting number of exercise sessions per week.
14) What is the benefit of interpreting standardized beta weights? (see p. 264).
15) What happens if your predictor variables are too closely correlated?
16) Reflect on your learning. What has been the most difficult? How did you get through it? What concepts are still fuzzy to you? Is there anything you could share with me that would help me address how you learn best?
3.AP Chem AB FRQ
A sample consisting of 50. mL of 0.400 M solution of the acid, HClO4, is titrated
titrated with a 0.200 M solution of the base, LiOH.
Write the balanced chemical reaction for neutralization reaction:
HClO4 (aq) + LiOH (aq) → LiClO4 (aq) + H2O (l)
Write the NET ionic equation for the neutralization reaction.
OH⁻ (aq) + H⁺ (aq) → H2O (l)
Compute the pH of the titration solution. Show your work
i) before any of the base is added
ii) after 25. mL of base is added
iii) after 50. mL of base is added
A student performs the titration with the same chemicals but with smaller volumes of each chemical . Which of the following titration curves could represent the titration. Explain
A because this entails a strong acid and a strong base.
A student performs a titration of an unknown acid with a strong base and gets the following titration curve:
a) The student consults the list of pKa of acids shown below. If the acid is listed in the table below, which is the most likely identity of the unknown acid? Explain.
7.2 x 10-4
1.8 x 10-5
4.3 x 10-7
2.0 x 10-9
The unknown acid is HBrO because the calculated Ka is in between 50^-4 and 50^-6 and 2.0 x 10^-9 lies in between them.
b) What is the initial molarity of the acid?
10^-3 = 0.001M
a) Describe the components and the composition of an effective buffer solution. Explain how the components of the buffer allow the buffer to maintain its pH.
An effective buffer solution has a weak acid and its conjugate base or a weak base and its conjugate acid. A buffer solution is most effective when the ratio of its component concentrations is close to 1, also when the pH is equal to the pka of the acid.; The components of the buffer allow the buffer to maintain its pH because buffers can absorb excess H+ions or OH– ions.
An employer is interviewing four applicants for a job as a laboratory technician and asks each how to prepare a buffer solution with a pH of 5.0. The following constants may be helpful: hydrazoic acid, pKa = 4.74 Boric acid, pKa = 9.23
Archita A. says she would mix equal molar solutions of hydrazoic (HN3) and sodium azide (NaN3) solutions.
Bradley B. says she would mix equimolar Boric acid (H3BO3) and HCl solutions.
Carlos C. says he would mix equimolar Boric Acid (H3BO3) and sodium dihydrogen borate (NaH2BO3) solutions.
Delia D. says he would mix equimolar hydrazoic Acid (HN3) and NaOH solutions.
b) Which of these applicants has given an appropriate procedure? Explain your answer
Delia because she is using Sodium hydroxide which results in a pH of 5. NaOH is a strong base and in order to have an effective buffer a weak acid must be incorporated which is the HN3.
c) Explain what is wrong with the erroneous procedures.
The rest all incorporate a strong acid and a strong base or a weak acid and a weak base which don’ result in an effective buffer.
d) The applicants have access to the 1 Liter volumes of each of the solutions listed above. They have access to graduated cylinders. In order to make 1.0 Liter of the correct 5.0 buffer solution, what volumes of the two chemicals must be mixed?
4.Hello guys, I confess that I absolutely suck at math. Unfortunately my boss handed me what is basically a math
lly a math problem I gotta solve, and I have no idea how to do it cause of lack of my math skills. I am hoping someone can help me with this or I'm screwed.
Co basically I've got this table in excel, where X (row) is a width and Y is a height (column) of a wooden sauna cabin, the X;Y is the price for a sauna with said dimensions. I need to find a relationship between the size of the sauna and the price And formulate ani equation. I can't seem to find it, the price seems to grow non linearly, I can't seem to find any coeficient. Again, I suck at math, maybe solution is simple, but I just don't see it. Can anyone help me please?
Table Is at this link https://ibb.co/fGrxSvf . Thanks for any help!
5.In a simple reaction A ↔ A*, a molecule is interconvertible between two forms that differ in standard free energy
ard free energy G° by 18 kJ/mole, with A* having the higher G°.
Use the table below to find how many more molecules will be in state A* compared with state A at equilibrium.
If an enzyme lowered the activation energy of the reaction by 11.7 kJ/mole, how would the ratio of A to A* change?
Table: RELATIONSHIP BETWEEN THE STANDARD FREE- ENERGY CHANGE, ∆G°, AND THE EQUILIBRIUM CONSTANT
Hint: ∆G° represents the free-energy difference under standard conditions (where all components are present at a concentration of 1 mole/litter). From this table, we see that if there is a favourable free-energy change of –17.8 kJ/mole for the transition Y→ X, there will be 1000 times more molecules of X than of Y at equilibrium (K = 1000).
6.given this table figure out:
"Are the frequency distribution of mask types the same across the six cities?" In other
cities?" In other words, "do people in the 6 cities wear the different mask types with similar likelihood?"
Let's say you have 4 types of masks: N95, pleated blue polyester, cloth, neck gaiter. Then you'll have a data table that is 4x6 with how many degrees of freedom? With this table you only have one overall H0: the dist'n of mask types is the same for all 6 cities. The corresponding H1 is "at least one city is not like the others."
What happens if you have a violation of Cochran's Rule among the 24 expected values? What will you do?
7.1. Which visual representation is false? *
2. Choose the pair of numbers √15 is between. *
3. Which shows the
3. Which shows the following numbers in order from least to greatest? *
4. Which is the best name for this group of numbers? *
5. Which point on the number line best represents √3? *
For question 6 and 7, write each number in either scientific notation or standard notation. 6. The diameter of Mercury is 4879 kilometers. *
7. The diameter of a bacterial cell called a mycoplasma is about 2 x 10-7 meter. *
8. In which group are the numbers in order from greatest to least? *
9. Greg found the length of a hypotenuse of a right triangle to be √90 feet. Between which two integers does √90 lie? *
10. Which is the best name for this group of numbers? *
11. The water levels of five Texas lakes were measured on the same day in 2010. The table below shows the number of feet above or below normal level for each lake. Which list shows the numbers in the table from greatest to least? *
12. Which numbers from this list are less than -0.94? *
13. The length of a micrometer is approximately 0.00003937 inch. How would you express this in scientific notation? *
14. The National Park Service manages approximately 84,000,000 acres of federal land. How would you express this number using scientific notation? *
15. Seismosaurus is the longest known dinosaur. It measured 1800 inches. How far would 3000 Seismosaurus dinosaurs span if they were placed head to tail? Write your answer in scientific notation. *
8.Hello I have two problems to solve the subject is Quantitative Methods for Decision-Making
After graduating from AUD, Salman plans
After graduating from AUD, Salman plans to start a book publishing company in the Media City. He did some research and found that the printer will cost Dh 230,000. He estimated that the variable cost per book is Dh 170 and the selling price is Dh 390.
a. How many books must he sell to break even? Also calculate the breakeven in dirham.
b. In addition to the costs given above, if he wants to pay himself a salary of Dh 15,400 per year, what is her breakeven point in units and dirham?
c. In the first three months of his business, he sold 400 books. Suddenly the printer breaks down. He spent Dh 25000 to fix the printer. In addition to 400 books sold, how many more books she should sell to breakeven? Assume that this part of the question is independent, and she does not draw any salary.
A furniture store makes tables and chairs from plywood and glass. The store has 30 units of plywood, 24 units of glass. Each table requires 7 units of plywood three units of glass, whereas each chair requires three units of plywood and two units of glass. The demand for chairs is between 2 and 4. The ratio between the table and chair is at least 1 to 2. A table earns $225 in profit and a chair, $145. The store also wants a minimum profit of $5000. The store wants to determine the number of tables and chairs to make in order to maximize profit. Formulate a linear programming model for this problem