Question

what is the independent variable in an experiment?
a. the factor that is kept constant
b. the factor that is measured
c. the outcome of the experiment
d. the factor that is deliberately changed or manipulated

why is it important to have a clear hypothesis before starting an experiment?
a. to avoid collecting data
b. to guide the direction of the experiment
c. to speed up the experiment
d. to ensure the experiment fails

why is it important to keep controlled variables constant?
a. to change the outcome of the experiment
b. to confuse the results
c. to make the experiment more interesting
d. to ensure the results are due to the independent variable alone

if a plant grows taller due to increased sunlight, what is the dependent variable?
a. the amount of sunlight
b. the type of fertilizer
c. the height of the plant
d. the type of soil

Explanation:

First Question:

• Option a: Constant factors are controlled variables, not independent.
• Option b: Measured factor is dependent variable.
• Option c: Outcome is dependent variable.
• Option d: Independent variable is manipulated by the experimenter.

• Option a: Hypothesis helps in data collection (what to measure/observe), so "avoid" is wrong.
• Option b: Hypothesis gives direction (what to test, how to design experiment).
• Option c: Hypothesis doesn’t speed up; it guides design.
• Option d: Hypothesis aims to test, not ensure failure.

• Option a: Changing outcome is not the goal of controlled variables.
• Option b: Controlled variables reduce confusion, not cause it.
• Option c: Controlled variables are for validity, not interest.
• Option d: Keeping controlled variables constant isolates the effect of independent variable on dependent variable.

Answer:

d. The factor that is deliberately changed or manipulated

Second Question: