Scientific Method and Water Quality Vs

Exercise 1: Data Interpretation
Table 1: Water Quality vs. Fish Population
Dissolved Oxygen
0
2
4
6
8
10
12
14
16
18
Number of Fish Observed
0
1
3
10
12
13
15
10
12
13

1. What patterns do you observe based on the information in Table 1?

As dissolved oxygen is increasing the number of fish are being observed more. When dissolved oxygen is at 12, the number of fish observed peaked at 15 and then falls.

2. Develop a hypothesis relating to the amount of dissolved oxygen measured in the water sample and the number of fish observed in the body of water.

The increase of dissolved oxygen will increase the number of fish.

3. What would your experimental approach be to test this hypothesis?

Have two fish tanks connected by a small tube. I’ll have both fish tanks with bad water quality. One of the fish tanks will slowly increase its water quality by using a filter.

4. What are the independent and dependent variables?

The independent variables are the number of fish observed and the dependent are the dissolved oxygen

5. What would be your control?

The fish that are in the tank without the filter.

6. What type of graph would be appropriate for this data set? Why?

Line graph because it gives an outlook of the increase of dissolved oxygen and the number of being observed

7. Graph the data from Table 1: Water Quality vs. Fish Population (found at the beginning of this exercise). You may use Excel, then “Insert” the graph, or use another drawing program. You may also draw it neatly by hand and scan your drawing. If you choose this option, you must insert the scanned jpg image here.

8. Interpret the data from the graph made in Question 7.

The graph shows the dissolved oxygen has a steady increase. Meanwhile, The number of fish observed increase then suddenly drop. After the lost of 5 fish, it increases again.

Exercise 2: Testable Observations

Determine which of the following observations could lead to a testable hypothesis.
For those that are testable:
Write a hypothesis and null hypothesis
What would be your experimental approach?
What are the dependent and independent variables?
What is your control?
How will you collect your data?
How will you present your data (charts, graphs, types)?
How will you analyze your data? 1. When a plant is placed on a window sill, it grows three inches faster per day than when it is placed on a coffee table in the middle of the living room.

Hypothesis: A plant will grow quicker on a window sill than in the middle of the living room.
Approach: Monitor one plant on the window sill and another on the coffee table. I will report each day how many inches each plant grows.
Independent Var: The amount of inches each plant will grow each day
Dependent Var: The amount of days I reported.
Control: The plant that’s indoor will grow slower
Collect: I will report each day how many inches each plant grows
Present: The use of a line graph will help show the growth of both plants
Analyze: I will monitor both plants in how they grew with or without sunlight. Also, if outside temperature made a difference with room temperature.

2. The teller at the bank with brown hair and brown eyes and is taller than the other tellers.

Not Testable because there’s no theory. Its been proven. 3. When Sally eats healthy foods and exercises regularly, her blood pressure is 10 points lower than when she does not exercise and eats unhealthy foods.

Hypothesis: Sally’s healthy diet and regular exercises will give her lower blood pressure if she was to not exercise and not have a diet.
Approach: For 30 days Sally will have a strict diet and exercises regularly. For another 30 days, have no diet and do not exercise.
Independent Var: Sally’s Blood Pressure for each day
Dependent Var: The amount of days on diet and off diet.
Control: The diet that’s being followed and intensity of the exercises.
Collect: I will report each day sally’s daily blood pressure.
Present: The use of a line graph will help show Sally’s blood pressure whether it’s decreasing or increasing.
Analyze: I will determine if Sally blood pressure is lower or higher when she is on a healthy diet and exercises regularly.

4. The Italian restaurant across the street closes at 9 pm but the one two blocks away closes at
10 pm. Non-testable because businesses have a consistent close of business.

5. For the past two days the clouds have come out at 3 pm and it has started raining at 3:15 pm.
Non-Testable because weather patterns change all the time.

6. George did not sleep at all the night following the start of daylight savings.
Non-testable because it’s proven he did not sleep.
Exercise 3: Conversion
For each of the following, convert each value into the designated units. 1. 46,756,790 mg = __4.6_kg
2. 5.6 hours = _20,160 seconds
3. 13.5 cm = ___5.3_ inches
4. 47 °C = _116.6 °F

Exercise 4: Accuracy and Precision – Label each of these conditions as Precise, Accurate, Both or Neither.
1. During gym class, four students decided to see if they could beat the norm of 45 sit-ups in a minute. The first student did 64 sit-ups, the second did 69, the third did 65, and the fourth did 67.
Both
2. The average score for the 5th grade math test is 89.5. The top 4th graders took the test and scored 89, 93, 91 and 87.
Neither because different grades
3. Yesterday the temperature was 89 °F, tomorrow it’s supposed to be 88°F and the next day it’s supposed to be 90°F, even though the average for September is only 75°F degrees!
Neither
4. Four friends decided to go out and play horseshoes. They took a picture of their results shown to the right:
Both

5. A local grocery store was holding a contest to see who could most closely guess the number of pennies that they had inside a large jar. The first six people guessed the numbers 735, 209, 390, 300, 1005 and 689. The grocery clerk said the jar actually contains 568 pennies.
Neither

Exercise 5: Significant Digits and Scientific Notation
Part 1: Determine the number of significant digits in each number and write out the specific significant digits. 1. 405000 (3) 405
2. 0.0098 (2) 98
3. 39.999999 (8) 39999999
4. 13.00 (2) 13
5. 80,000,089 (8) 80000089
6. 55,430.00 (4) 5543
7. 0.000033 (2) 33
8. 620.03080 (7) 62003080 Part 2: Write the numbers below in scientific notation, incorporating what you know about significant digits. 1. 70,000,000,000 7.0 * 10^10
2. 0.000000048 4.8 * 10^8
3. 67,890,000 6789 * 10^7
4. 70,500 705* 10^4
5. 450,900,800 4.509008 * 10^8
6. 0.009045 9.045 * 10^ -3
7. 0.023 2.3 * 10^ -2