Question

Sample Hypotheses 1. If the rate of skin cancer occurrence is related to exposure to ultraviolet light, then people with a high exposure to UV light will have a higher frequency of skin cancer. Independent variable - Dependent variable - Confounding variable - 2. If the color of the leaves on a tree change because of changes in temperature, then exposing plants to low temperatures will result in changes in leaf color. Independent variable Dependent variable Confounding variable - 3. If baking powder is the ingredient responsible for causing batter to rise in pancakes, then varying the amount of baking powder will result in different heights of the final product (with an upper limit defined by the law of diminishing returns). Independent variable - Dependent variable - Confounding variable - 4. If the load of sediment in a river is related to the velocity of the water in the river, then the slower the water, the less sediment it will contain. Independent variable- Dependent variable - Confounding variable- 5. If the speed of seed germination is related to the hardness of the hull of the seed, then softening the seed with water or a weakly acidic solution prior to planting will speed up germination. Independent variable Dependent variable Confounding variable -

Answer 1

ANSWER.

* Independent variable.

             Variables which are changed by a researcher is called

            independent variable.

* Dependent variables.

              Variables that change due to the manipulation of independent

              variables is called dependent variable.

* Confounding variable.

              External influences which can affect the relationship between

              independent and dependent variables is called confounding

              variables.

1) Independent variable ; Exposure to ultraviolet light.

     Dependent variable ; Rate of skin cancer.

Confounding variable ; People with a higher exposure to UV light.

2) Independent variable ; Changes in temperature.

    Dependent variable ; Changes in color of leaves on a tree.

    Confounding variable ; Exposing plants to low temperature.

3) Independent variable ; Baking powder.

    Dependent variable ; Rise in pancakes.

    Confounding variable ; Varying the amount of backing powder.

4) Independent variable ; Velocity of water in the river.

    Dependent variable ; Load of sediment in the liver.

    Confounding variable ; Slower the velocity of water.

5) Independent variable ; Hardness of hull of the water.

    Dependent variable ; Speed of seed germination.

    Confounding variable ; Softening of seed with water or weakly

                                       acidic solution prior to planting.