Objectives

To become familiar with the uses of Radioisotopes through use of the Internet.

To be able to use your knowledge and understanding of radioisotopes to contribute to the discussion board.

Background

According to our textbook, “radioisotopes are powerful tools for studying processes in biochemistry, medicine, material science, environmental studies and many other scientific and industrial fields.”

Below is a list of radioisotopes and their half-lives. You will be choosing one of these radioisotopes to explore in more detail.

Assignment

Choose one of the radioisotopes from the list or find a radioisotope that is not on the list but interests you.

Using your book and Internet resources, find five interesting pieces of information on the radioisotope you selected. Suggested pieces of information may include:

How is the radioisotope formed in nature (type of decay)?

Risks associated with the radioisotope

Number of subatomic nucleons present

Stability of the radioisotope

How this radioisotope is used.

Is the radioisotope used as a medical tracer? If yes, for what body part or process? Briefly explain.

(These are just a few suggestions. See if you can find other interesting facts.)

Remember to site your sources in APA style.

Respond to at least two other students.

Contribute to an ongoing discussion by responding to comments made to your posting or to comments made by other students to other postings.

Radioisotopes (half-life indicated)

Molybdenum-99 (66 h)

Technetium-99m (6 h)

Bismuth-213 (46 min)

Chromium-51 (28 d)

Cobalt-60 (10.5 mth)

Copper-64 (13 h

Dysprosium-165 (2 h

Erbium-169 (9.4 d)

Holmium-166 (26 h)

Iodine-125 (60 d)

Iridium-192 (74 d)

Iron-59 (46 d)

Lutetium-177 (6.7 d)

Palladium-103 (17 d)

Phosphorus-32 (14 d)

Potassium-42 (12 h)

Rhenium-186 (3.8 d)

Rhenium-188 (17 h)

Samarium-153 (47 h)

Selenium-75 (120 d)

Sodium-24 (15 h)

Strontium-89 (50 d)

Xenon-133 (5 d)

Ytterbium-169 (32 d)

Yttrium-90 (64 h)

Carbon-11 (20 m)

Nitrogen-13 (~10 m)

Oxygen-15 (~2 m)

Fluorine-18 (20 m)

Cobalt-57 (272 d)

Gallium-67 (78 h)

Indium-111 (2.8 d)

Iodine-123 (13 h)

Rubidium-82 (65 h)

Strontium-92 (25 d)

Thallium-201 (73 h)

Eight students (Anna, Brian, Carol, ...) are to be seated around a circular table with eight seats, and two seatings are considered the same arrangement if each student has the same student to their right in both seatings.(a) How many arrangements of the eight students are there?(b) How many arrangements of the eight students are there with Anna sitting next to Brian?(c) How many arrangements of the eight students are there with Brian sitting next to both Anna and Carol?(d) How many arrangements of the eight students are there with Brian sitting next to either Anna or Carol?

please explain how u got the numerical answer for each part, like what you multiplied to get it

An article was released claiming that students study a mean of 250 hours per semester. You want to gather data to prove that the mean study time per semester for students is actually more than 250 hours. You take a sample of the students and find their mean study time to be 265 hours per semester with a standard deviation of 70 hours. Answer the following questions using α = .1

a) State the null and alternative hypotheses.

State the rejection rule, find the test statistic, and conclude whether or not you reject the null hypothesis (and with how much confidence) if:

b) the sample consisted of 25 students.

c) the sample consisted of 100 students.

Retention of students after freshman year is always important at SMC.    The college noticed after 2018 that the rat of retention was 78%.  So in 2019 they have decided to implement new policies toward increasing student retention.  After the first year of the policy there were 342 first time first year students of which 278 returned for the second year of studies.  Treat these students as a random sample of all first time first year students.  Did a statistically significant higher proportion of students return for their second year under this policy?  Use alpha level = .1   In other words do you believe the results are significant enough that these changes be made permanent?

The IQ scores of MBA students follow a normal distribution with a population mean of 120 points and a population standard deviation of 12. A random sample of 36 MBA students is chosen.

1. What is the probability that a randomly chosen sample of 36 MBA students has an average IQ less than 115?

2. What is the 91st percentile of sample average IQ’s of size 36 taken from the population of MBA students?

3. Calculate the bounds that determine the middle 72% of sample average IQ’s of size 36 taken from the population of MBA students?

1. 120 + 0.5284
2. 120 + 0.72
3. 120 + 1.28
4. 120 + 2.16
5. 120 + 12.96

Suppose we have assigned grades for the 11 students in our data: Grade A for students who scored ≥ 90; B for students who scored ≥ 80 and < 90; C for students who scored ≥ 70 and < 80; D for students who scored ≥ 60 and < 70; F for students who scored < 60.
Following the above grade scheme, we observe that we have
8 students who received grade A,
2 student received grade B,
0 students received grade C,
0 students received grade D and
1 student received grade F. Using this, please answer the following questions:

#1. Impact Evaluation

   In the move to online instruction due to COVID-19, Development University was concerned that its students may not have the technology they needed at home to keep up with their classes. In order to address this issue, at the start of the term, the University offered all students coupons for a 50% price discount on a new iPad. The hope was that the iPad would allow students to participate more fully in their online classes, and therefore allow them to learn more.

    Development University heard that you have learned how to do impact evaluation in your economics classes, so asked you to evaluate how well the iPads worked for their students. In particular, they wanted to know if the iPads caused student grades to improve. In looking at the data, you notice that although all students were offered the coupon, only half of them purchased an iPad through the program. Therefore, you decide to compare the average GPAs of students who purchased an iPad to those who didn't. You find that students who purchased an iPad had an average GPA of 3.4, and students who did not purchase an iPad had an average GPA of 3.1.

1) Due to your concerns, Development University decides to conduct a randomized control trial with incoming students in the fall. That is, incoming students are randomly assigned to either receive a coupon for a discounted iPad, or to not receive a coupon.

Will this research design allow you to estimate the true Average Treatment Effect of iPads on student performance? Why or why not?

2) In three sentences or less, briefly describe one concern you may still have with this randomized design.

1. For all U.S. students nationally who take the SAT, SAT Math scores are normally distributed with an average score of 500 for all U.S. students. A random sample of 100 students entering Whitmer College had an average SAT Math (SAT-M) score of 475 and a sample standard deviation of 120. The sample data can be used to test the claim that the mean SAT-M score of all Whitmer College students is different than the national mean SAT-M score. Based on the given information and using the appropriate formula, calculate the test statistic for this hypothesis test. Round your answer to two decimal places. Enter the numeric value of the test statistic in the space below:

2. A survey administered to a random sample of 400 U.S. college students found that 40 out of the 400 students surveyed were a member of a sorority or a fraternity. Compute a 99% confidence interval for the proportion of U.S. college students who are a member of a sorority or a fraternity. In the blank below, enter the upper bound of the 99% confidence interval for p. For example, if your confidence interval is (0.115, 0.276), the upper bound would be 0.276. Provide your answer as a decimal rounded to three decimal places.

3. A survey administered to a random sample of 400 U.S. college students found that 40 out of the 400 students surveyed were a member of a sorority or a fraternity. Compute a 90% confidence interval for the proportion of U.S. college students who are a member of a sorority or a fraternity. In the blank below, enter the upper bound of the 90% confidence interval for p. For example, if your confidence interval is (0.115, 0.276), the upper bound would be 0.276. Provide your answer as a decimal rounded to three decimal places.

Suppose that you want to measure the causal effect of hours spent studying on the performance on a microeconomics test for a class of 30 students.

Which of the following could be an ideal randomized controlled experiment to study the desired causal​ effect?

A.

Allow the fifteen students with the highest grades in the class an extra day to study for the microeconomics test. Then measure the test score differences between students who got the extra day to study and those that did not.

B.

Allow all students an extra day to study for the microeconomics test. Then measure the test score difference between the student with the highest score and lowest score respectively.

C.

Allow fifteen​ students, chosen at​ random, an extra day to study for the microeconomics test. Then measure the test score differences between students who got the extra day to study and those that did not.

D.

All of the above could be ideal randomized controlled experiments.

Consider the following randomized controlled​ experiment:

You allow fifteen​ students, chosen at​ random, an extra day to study for the microeconomics​ test, and then measure the score differences between those who got the extra day to study and those that did not.

Which of the following could be impediments to implementing this experiment in​ practice?

A.

It could be costly to administer the same test to two different groups of students in the same class on different days.

B.

It could be considered unethical to allow some students more time to study.

C.

It could be against school policy to administer the same test to two different groups of students in the same class on different days.

D.

A and C only.

E.

All of the above could be impediments to implementing this experiment in practice.

Are U-Albany students more likely to approve gun control than adults in the U.S.? According to a research report, on a scale from 1 to 10, the mean approval of gun control in the U.S. is 7.8. The mean approval of gun control in a random sample of 26 U-Albany students is 8.3, with the standard deviation of 2.2. Use α = 0.01 for the hypothesis testing. Questions 28 to 32 are based on this example.
28. What would be the H0 for the example?
A. U-Albany students are equally likely to approve gun control than adults in the U.S.
B. The likelihood of approving gun control among U-Albany students is different from that of the U.S. adults.
C. There is no difference between the 26 U-Albany students and all U.S. adults in terms of their attitudes toward gun control.
D. U-Albany students are less likely to approve gun control than adults in the U.S.

29. What would be the t critical value(s)?

30. What’s the standard error based on the sample information?

31. What is the t obtained value?

32. What conclusion can we make for this example?
A. We cannot reject the null hypothesis that the mean approval of gun control among the 26 U-Albany students is 8.3.
B. There is no enough evidence to reject the null hypothesis that the mean approval of gun control among U-Albany students is 8.3.
C. We cannot reject the null hypothesis that the mean approval of gun control among all U-Albany students is 7.8.
D. We can reject H0 and accept H1 that the mean approval of gun control among all U-Albany students is larger than 7.8.