Question

d. a study was done to find if different tire treads affect the braking distance of a car.
manipulated variable:
responding variable:
control:

e. the time it takes to run a mile depends on the persons running speed.
manipulated variable:
responding variable:
control:

f. the height of bean plants depends on the amount of water they receive.
manipulated variable:
responding variable:
control:

g. the higher the temperature of the air in the oven, the faster a cake will bake.
manipulated variable:
responding variable:
control:

Explanation:

D

• Manipulated Variable: The factor we change, here it's tire treads (different types are tested).
• Responding Variable: The factor we measure, which is the braking distance (affected by tire treads).
• Control: Factors kept constant, like the car model, road conditions, speed before braking, etc. (to ensure only tire treads affect braking distance).

• Manipulated Variable: The variable we adjust, which is running speed (we change how fast a person runs).
• Responding Variable: The variable we observe/measure, which is the time to run a mile (depends on running speed).
• Control: Factors like the person (same individual or similar fitness), the mile route (same track/road), weather conditions, etc. (to isolate the effect of speed on time).

• Manipulated Variable: The variable we manipulate, which is the amount of water (we change how much water the bean plants get).
• Responding Variable: The variable we measure, which is the height of bean plants (depends on water amount).
• Control: Factors like type of bean plant, soil type, sunlight exposure, temperature, etc. (to ensure only water affects plant height).

Answer:

Manipulated Variable: Tire treads
Responding Variable: Braking distance of the car
Control: Car model, road conditions, initial speed, etc.

E