Two different ant species, Pseudomyrmex and Myrmica, are sometimes found together on the branches of acacia trees. Researchers remove all Pseudomyrmex from one acacia tree. They observe that after removal, the population of Myrmica begins to increase.

From another acacia tree, they remove all Myrmica, and notice that this has apparently no effect on the population of Pseudomyrmex.

Several weeks later, the researchers observe that the tree with no Pseudomyrmex has been grazed to a stump by local tapirs. The tree with no Myrmica and all the acacias with both ant species, remain un-grazed.

In order to test whether there is a mutualistic relationship between acacia trees and Pseudomyrmex, what additional experiment needs to be done?

A

None, the evidence from this observation is enough.

B

A removal experiment in which Pseudomyrmex is placed on a different species of tree

C

A removal experiment in which both species of ant are placed on a different species of tree

D

A laboratory analysis of the chemicals produced by the tree

E

A removal experiment in which tapirs are kept away from the tree

What type of effect might Pseudomyrmex be having on the tapirs?

A

direct positive

B

direct negative

C

indirect positive

D

neutral

1. According to the article, the data was collected through the following means: “For the study, 1,633 participants provided baseline estimates of hand hygiene behaviour and coronavirus infections were identified from nasal swabs…At the start of each season, participants were asked to estimate how many times they had washed their hands the previous day. Frequency of daily hand-washing was subsequently categorized as low, zero to five times daily, moderate, six to 10 times daily, or high, more than 10 times daily.”  

1. Explain why this is an observational study, not an experiment.

2. Identify any potential sources of error in data collection.

3. If scientists were to do this as an experiment, how could they do it? Be specific and address the following concerns.

1. Identify the explanatory variable

2. Identify the response variable

3. Identify how you would choose participants to avoid bias. Consider different types of bias

4. Give a procedure for how the experiment would be run

5. Identify one thing that would be directly controlled

6. Identify an extraneous variable being controlled by random assignment.

7. Would there be a placebo in this experiment? Why or why not?

(I WILL GIVE HIGH RATING I PROMISE)

6. There are 40 books on a bookshelf. Exactly 10 of them have a red cover. The remaining books have a white cover. You intend to choose a random sample of nine books, but you haven't decided whether to choose with replacement or without replacement?

a) If you choose books with our placement, would this procedure lead to independent trials or dependent trials?

b)if you choose books with replacement, would this procedure be consistent with a binomial experiment or not?

c) what is the size of the population? show your work

d) what is the size of the sample? show your work

e) if you ultimately conduct a binomial experiment, find the probability that the 5th book you select, happens to have a red cover? please show your work

f) if you ultimately conduct a binomial experiment, find the probability that you choose two or more red-covered books? please show your work

Finally, for a binomial experiment, please determine: show your work

1. average number of red books, per sample of nine books?
2. the variance of the number of red books, per sample of nine books?

18. One factor that affects the rate of diffusion is_________________________ this factor is

DIRECTLY/ INDERCETLY/ (Circle one) proportional to the rate of diffusion.

19. Listed below are data from osmosis experiment, similar to the one toy conducted in lab a few weeks ago…. Different concentrations were tested and the percent weigh change was measured. Unfortunately, your partner forgot to label the sucrose beakers!

   Percent weight change Data (Mixed up!) +5.3% ; -27.8 ; -7% ; +11.2% ; and -17.5 %

A. Based on what you know about osmosis, match each percent Wt. change with the appropriate / correct OAS concentration.

       Concentration                                    % Wt. change

       .5 M               _________________              

.4 M               _________________               

.3 M               _________________             

.2 M               _________________             

.1 M               _________________                

O M               _________________          

B) Which concentration(s) was/were hypertonic to the potatoes cells?

Experimental design & the scientific method

20. You and your lab partner have decided to address the following question: what is the effect of a high protein diet on the growth of Guinea pigs?

A) What would be an appropriate hypothesis to address the following question?

B) You have decided to do an experiment in which you give four groups of guinea pigs of different amounts of proteins in their diet for four week-period.

What is your independent variable for this experiment? ________________________________

What is your dependent variable for this experiment?   _________________________________

Write an appropriate prediction if your hypothesis is to be supported by the data

21. You carry an experiment in which different batches of seeds are soaked in 5 different salt solutions of decreasing concentration and the percent germination is determined for each batch after 14 days.

Following are selected transactions of Danica Company for 2016 and 2017. 2016 Dec. 13 Accepted a $18,000, 45-day, 6% note dated December 13 in granting Miranda Lee a time extension on her past-due account receivable. 31 Prepared an adjusting entry to record the accrued interest on the Lee note. 2017 Jan. 27 Received Lee's payment for principal and interest on the note dated December 13. Mar. 3 Accepted a $12,000, 6%, 90-day note dated March 3 in granting a time extension on the past-due account receivable of Tomas Company. 17 Accepted a $10,000, 30-day, 8% note dated March 17 in granting H. Cheng a time extension on his past-due account receivable. Apr. 16 H. Cheng dishonored his note when presented for payment. May 1 Wrote off the H. Cheng account against the Allowance for Doubtful Accounts. June 1 Received the Tomas payment for principal and interest on the note dated March 3. Complete the table to calculate the interest amounts and use those calculated values to prepare your journal entries. (Do not round intermediate calculations. Use 360 days a year.)

1. If the change in GDP in South Korea from 2016 Quarter 3 to 2016 Quarter 4 was 6%, then we may conclude that the s.a.a.r for GDP in the same period was

1. 1.6%, because s.a.r. measures quarter-to-quarter growth
2. 3.2%, because s.a.a.r. measures the upper limit of current GDP growth
3. One-fourth of 1.6%, or 0.4%, because s.a.a.r. removes all annualized data
4. Four times 1.6%, or 6.4%, because s.a.a.r. annualizes quarterly data

2. The difference between an economic indicator being a flow variable rather than a stock variable is that

1. A flow refers to measuring a variable over time, while a stock measures a variable at a point in time
2. A flow refers to measuring a variable at a point in time while a stock measures a variable in non-monetary units
3. A flow refers to measuring a variable over time while a stock measures a variable in monetary units only
4. A stock is a measure of a variable over time while a flow measures a variable at a point in time

3. The level of potential GDP used as the benchmark comparison in assessing the long-run prospects of an economy is computed as:

1. The growth in labor force plus the growth in productivity plus the growth in hours worked
2. The growth in productivity plus the growth rate of the population
3. The growth rate of population plus the growth rate of current production
4. The growth rate of current production plus the growth rate of productivity plus the growth rate in hours worked

Following are selected transaction of Danica Company for 2016 and 2017.

2016

December 13 Accepted a $16,000, 45-day, 8% note dated December 13 in granting Miranda Lee a time extension on her past-due account receivable.

Dec 31 Prepaid an adjusting entry to record the accured interest on the Lee note

2017.

Jan 27 Received Lee's payment for principal and interest on the note dated December 13.

March 3 Accepted a $10,000, 6%, 90-day note dated March 3 in granting a time extension on the past-due account receivable of Tomas Company.

March 7 Accepted a $8,000, 30-day, 6% note dated March 17 in granting H. Cheng a time extension on his past-due account receivable

April 16 H. Cheng dishonored his note when presented for payment

May 1 Wrote off the H. Cheng account against the Allowance for Doubtful Accounts.

June 1 Received the Tomas payment for principal and interest on the note dated March 3.

Complete the table to calculate the interests amounts and use those calculated values to prepare your journal entries

(Do not round intermediate calculations. use 360 days a year)

M Lee Note-Complete the table to calculate the interest amounts. (Total through maturity- Amount Accrued at December 31-Interest Recognized January 27)

Tomas Co Note and H. Cheng Note

Complete the table to calculate the interest amount on Both companies. (Principal, Rate %, Time, Total Interest) Then use the calculated values to prepare your journal entries. PLEASE SHOW YOUR WORK

ollowing are selected transactions of Danica Company for 2016 and 2017. 2016 Dec. 13 Accepted a $26,000, 45-day, 6% note dated December 13 in granting Miranda Lee a time extension on her past-due account receivable. 31 Prepared an adjusting entry to record the accrued interest on the Lee note. 2017 Jan. 27 Received Lee's payment for principal and interest on the note dated December 13. Mar. 3 Accepted a $20,000, 8%, 90-day note dated March 3 in granting a time extension on the past-due account receivable of Tomas Company. 17 Accepted a $18,000, 30-day, 8% note dated March 17 in granting H. Cheng a time extension on his past-due account receivable. Apr. 16 H. Cheng dishonored his note when presented for payment. May 1 Wrote off the H. Cheng account against the Allowance for Doubtful Accounts. June 1 Received the Tomas payment for principal and interest on the note dated March 3. Complete the table to calculate the interest amounts and use those calculated values to prepare your journal entries. (Do not round intermediate calculations. Use 360 days a year.)