Question

1. some snapdragon seeds were studied in the experiment above. the seeds were placed in a dish lined with a moist paper towel. which of these is the independent (manipulated) variable in this experiment? a. the type of seed b. the amount of water used c. the number of sprouts d. the temperature of each dish 6. john and emily were experimenting with the effects of road salt on plant growth. to do this, they watered plants daily with the same amount of salt water. they could best improve their experiment by a. increasing the amount of salt added to the water each day b. cooling the salt water before watering the plants c. adding food color to see how far the salt penetrates the plants d. watering half the plants with pure water and half with salt water

Explanation:

For question 5, the independent variable is the factor that is deliberately changed in an experiment. Here, the temperature of each dish is being changed while other factors like seed - type and water - amount are likely kept constant. The number of sprouts is a dependent variable.
For question 6, to have a valid experiment to test the effects of road salt on plant growth, a control group is needed. Watering half the plants with pure water (control) and half with salt water (experimental) allows for a comparison.

Answer:

1. D. The temperature of each dish
2. D. watering half the plants with pure water and half with salt water