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. i think the indepent variable is sunflower ... variable is height measured and the control variable is the fourth plant.
<span>The mirror is used to focus light through the opening in the in the stage of the microscope.</span>
The answer for that is cell body. It goes in the blank.
Answer:
1. Today instead of rotating upright, The earth's axis is tilted 23.5 degrees. The angle varies a little over time, but the gravitational pull of the moon prevents it from shifting by more than a degree so. This tilt is what gives us seasons.
2.The cooling effects of more indirect sunlight cause autumn and winter. Because of the earth's approximately 23.5° tilt, the season in the northern and southern hemispheres reversed, about six months apart from each other.