Lactic acid is very good at penetrating the skin. Because of this, it is used in a number of products for skin care, such as exfoliating creams and chemical peels, and in formulations for transdermal delivery of medications, such as topical ointments and extended release patches for delivery through the skin. Lactic acid has a pKa of 3.86 in water at 25o C.

After graduation, you land your dream job at a small biotech firm specializing in novel antimicrobial agents. They have just developed a new drug, Poly-XSeption-L®, to help prevent antibiotic-resistant infections during local surgeries. Poly-XSeption-L® is to be applied to the skin at the site of the surgery in a liquid formulation containing lactic acid.

(a) The initial formulation being tested is a 1.0 wt% solution of Poly-XSeption-L® in a 0.015 M solution of aqueous lactic acid. Neglecting the effect of the antibiotic on the solution, what would you estimate the pH of this solution to be? State any assumptions you make.

(b) In clinical studies, it was found that the acidity of the initial formulation caused some problems with local irritation, and that Poly-XSeption-L® was not as effective below a pH of 4.2. It is proposed that sodium lactate be added to create a buffered solution with pH = 4.2. What concentration of sodium lactate should be used to achieve this pH?

Wolff Enterprises must consider several investment projects, A through E, using the capital asset pricing model (CAPM) and its graphical representation, the security market line (SML). Relevant information is presented in the following table

ITEM                            RATE OF RETURN                     BETA

Risk-free asset                          9%                                0.0

Market portfolio                       14%                              1.0

Project A                                  -                                   1.5

Project B                                   -                                   0.75

Project C                                   -                                   2.00

Project D                                  -                                   0.0

Project E                                   -                                   -0.50

1. Calculate (1) the required rate of return and (2) the risk premium for each project, given its level of nondiversifiable risk.
2. Use your findings in part a to draw the security market line (required rate of return relative to nondiversifiable risk)
3. Discuss the relative nondiversifiable risk of projects A through E.
4. Assume that recent economic events have caused investors to become less risk-averse, causing the market return to decline to 12%. Calculate the new required returns fcor assets A through E and draw the new security market line on the same graph you drew for b.
5. Compare your findings in parts a and b with those in part d. What conclusion can you draw about the impact of a decline in investor risk aversion on the required returns of risky assets?

An enzyme is discovered that catalyzes the chemical reaction

SAD --> <-- HAPPY

A team of motivated researchers set out to study the enzyme, which they call happyase. Under a constant enzyme concentration, [E] of 2.0 uM, they studied the relationship between substrate concentration [SAD] and reaction velocity V₀. Their data is shown below:

[SAD] (uM)                V₀ (uMs^-1)      

20                    3.4 x 10³

40                   5.4 x 10³

60                   6.6 x 10³

80                    7.4 x 10³

Can you determine K_cat and K_m from the above data?

2. While [E] remains 2.0 um and [SAD] = 12 uM, what would the reaction velocity V₀ be?

3. In a separate happyase experiment using [E] = 1.0 uM, the reaction velocity, V_0, is measured as 3.6 x 10³ uMs^-1. What is the [SAD] used in this experiment?

4.The researchers working on happyase discovered that the compound STRESS is a potent inhibitor of happyase. A kinetics study of happyase in the presence of         1 nM STRESS, gives the following data:

[SAD] (uM)                V₀ (uMs^-1)      

20                    1.7 x 10³

40                   2.7 x 10³

60                    3.3 x 10³               

80                    3.7 x 10³

Which class of inhibitors does STRESS belong to?

For the question below, state what your null and alternative hypotheses are and select the appropriate test. Assess assumptions and do whatever needs to be done depending on your results (ie, doing a transformation of data or selecting a non-parametric if data violate assumptions). If you decide to run a Kruskal-Wallis test, you can assume the data satisfy those assumptions. Recall that it is generally considered ok to violate one assumption, especially if sample size is not too small. Perform the test and report the p value with the biological interpretation of your data. Finally, make a plot of the data that DOES NOT have a title, but does have proper x and y axis labels (can do it in excel or SPSS).

1)

You are interested in the connection between vitamin C and bone health. You expose guinea pigs to three different doses of vitamin C and then you record tooth growth following the doses. You collect the following data which are measures of tooth length in mm.

Pierce Products Inc. is considering changing its capital structure. F. Pierce currently has no debt and no preferred stock, but it would like to add some debt to take advantage of the tax shield. Its investment banker has indicated that the pre-tax cost of debt under various possible capital structures would be as follows:

F. Pierce uses the CAPM to estimate its cost of common equity, r_s, and at the time of the analaysis the risk-free rate is 6%, the market risk premium is 7%, and the company's tax rate is 25%. F. Pierce estimates that its beta now (which is "unlevered" because it currently has no debt) is 1.4. Based on this information, what is the firm's optimal capital structure, and what would be the weighted average cost of capital at the optimal capital structure? Do not round intermediate calculations. Round your answers to two decimal places. What are the following percentages?

Debt:   %

Equity:   %

WACC:   %

The following data represent petal lengths (in cm) for independent random samples of two species of Iris. Petal length (in cm) of Iris virginica: x1; n1 = 35 5.3 5.7 6.5 6.1 5.1 5.5 5.3 5.5 6.9 5.0 4.9 6.0 4.8 6.1 5.6 5.1 5.6 4.8 5.4 5.1 5.1 5.9 5.2 5.7 5.4 4.5 6.4 5.3 5.5 6.7 5.7 4.9 4.8 5.8 5.2 Petal length (in cm) of Iris setosa: x2; n2 = 38 1.5 1.7 1.4 1.5 1.5 1.6 1.4 1.1 1.2 1.4 1.7 1.0 1.7 1.9 1.6 1.4 1.5 1.4 1.2 1.3 1.5 1.3 1.6 1.9 1.4 1.6 1.5 1.4 1.6 1.2 1.9 1.5 1.6 1.4 1.3 1.7 1.5 1.6 (a) Use a calculator with mean and standard deviation keys to calculate x1, s1, x2, and s2. (Round your answers to two decimal places.) x1 = s1 = x2 = s2 = (b) Let μ1 be the population mean for x1 and let μ2 be the population mean for x2. Find a 99% confidence interval for μ1 − μ2. (Round your answers to two decimal places.) lower limit upper limit

1. You are a consultant to the government of Zambonia.

You have the following information:

(1) Y = C + I + G + X - M

(2) C = 75 + 0.6Yd

(3) I = 125

(4) G = 81

(5) T = - 40+.35Y (tax equation)

(6) Yd = Y – T

(7) P is fixed at 1.0.

Note the T has two components: a lump-sum component (- 40) that is autonomous and not related to the level of Y; and a component that is related to the level of Y. The -40 not related to income would be, for example, a tax rebate where the government sends each tax payer a check.

Suppose the president of Zambonia tells you her economist estimate the production function for Zambonia to be: Y = 1.1K .3L .7 and full employment K and L are 500 respectively.

f. What level of government spending is needed to get the economy to full employment?

g. The president tells you she is up for re-election and to ensure re-election she wants mail checks to all tax payers. How much will this cost the government?

h. Suppose velocity is constant at 5.045 and the money supply is 93. Given the information presented, can the central bank push the economy to full employment? How and why?

Problem 5 –  

Using the data provided complete the following projected Balance Sheet for Mumford Inc. as of and for the year ended December 31, 2020. Credit (and total) sales were $2,100,000. (Type in your values)) The long term debt is all interest bearing. The total stockholders’ equity is a combination of issued common stock and retained earnings.                    Problem 5 is continued on the next page.

Total asset turnover                       2.4 times
Cash to total assets                            2%
Accounts receivable turnover        8.0 times
Inventory turnover                          10.0 times
Current ratio                                       2.0 / 1.0
Debt to total assets                            61%                 


Assets                                                                    Liabilities

Cash                                                                       Current Debt

Accounts Receivable                                              Long Term Debt

Inventory                                                                 Total Debt

Total Current Assets
                                                                       Stockholders’ Equity

Fixed Assets (net of depr)               Total Stockholders’ Equity

TOTAL ASSETS                                                          TOTAL LIABILITIES AND STOCKHOLDERS’ EQUITY                                                       

Problem 5 continued –  

Mumford Inc. is using a combination of debt and equity in its capital structure. Identify two specific pros and two specific cons of each form of capital (interest bearing debt and issued common stock) and reflect upon (briefly discuss) what makes the item you identified either a pro or a con. The remaining space on this page should be plenty of room for an effective answer.