Question

1. you water three sunflower plants with salt water. each plant receives a different concentration of salt solutions. a fourth plant receives pure water. after a two - week period, the height is measured.

independent variable:
dependent variable:
controlled variable:
controlled variable:
hypothesis:

1. three redwood trees are kept at different humidity levels inside a greenhouse for 12 weeks. one tree is left outside in normal conditions. height of the tree is measured once a week.

independent variable:
dependent variable:
controlled variable:
controlled variable:
hypothesis:

Explanation:

Step1: Identify independent variable for sunflower experiment

The variable that is changed is salt - water concentration.

Step2: Identify dependent variable for sunflower experiment

The variable that is measured is plant height.

Step3: Identify controlled variables for sunflower experiment

Factors like sunlight, temperature, pot size can be controlled.

Step4: Form hypothesis for sunflower experiment

A possible hypothesis could be: Higher salt - water concentration will lead to shorter sunflower height.

Step5: Identify independent variable for redwood experiment

The variable that is changed is humidity level.

Step6: Identify dependent variable for redwood experiment

The variable that is measured is tree height.

Step7: Identify controlled variables for redwood experiment

Factors like sunlight, soil type, tree age can be controlled.

Step8: Form hypothesis for redwood experiment

A possible hypothesis could be: Higher humidity levels inside the greenhouse will lead to greater redwood tree height.

Answer:

4.
Independent Variable: Concentration of salt solutions
Dependent Variable: Height of the sunflower plant
Controlled Variable: Sunlight exposure
Controlled Variable: Temperature
Hypothesis: Higher salt - water concentration will lead to shorter sunflower height

5.
Independent Variable: Humidity level
Dependent Variable: Height of the redwood tree
Controlled Variable: Sunlight exposure
Controlled Variable: Soil type
Hypothesis: Higher humidity levels inside the greenhouse will lead to greater redwood tree height