Question

scenario

1. a cow is given a growth hormone and then compared to another cow that was not given a growth hormone. both cows were weighed at 2 years old.
2. mosquito repellent is sprayed on one arm, and the other arm is not sprayed. the number of mosquito bites is counted after 2 hours.
3. one grape is placed in tap water, and another grape is placed in salt water. the change in their mass is measured after a day.
4. two different cars are traveling at 60 mph. at a certain point, both cars slam on the brakes. the distance it takes for each car to stop is then measured.
5. pillbugs are placed in a container where they have a choice of a wet or a dry environment. researchers record how much time was spent on each side.
6. a stapler is used to staple 100 papers; it jams 5 times during the trial. a different brand of stapler performs the same test; it jams 22 times.

Explanation:

Step1: Identify independent variable

The independent variable is the factor that is deliberately changed or manipulated in an experiment.

Step2: Identify dependent variable

The dependent variable is the factor that is measured or observed and is affected by the independent variable.

1.

• Independent variable: Growth hormone (given or not given)
• Dependent variable: The weight of the cows

2.

• Independent variable: Mosquito - repellent (sprayed or not sprayed)
• Dependent variable: The amount of mosquito bites

3.

• Independent variable: Type of water (tap water or salt - water)
• Dependent variable: The change of mass

4.

• Independent variable: Type of car
• Dependent variable: The distance it takes for the car to stop

5.

• Independent variable: Environment type (wet or dry)
• Dependent variable: The time spent on each side

6.

• Independent variable: Brand of stapler
• Dependent variable: The number of jams

Answer:

1. Independent variable: Growth hormone; Dependent variable: The weight of the cows
2. Independent variable: Mosquito - repellent; Dependent variable: The amount of mosquito bites
3. Independent variable: Type of water; Dependent variable: The change of mass
4. Independent variable: Type of car; Dependent variable: The distance it takes for the car to stop
5. Independent variable: Environment type; Dependent variable: The time spent on each side
6. Independent variable: Brand of stapler; Dependent variable: The number of jams