The principal ingredient of glass is quartz sand (SiO₂).
Answer:
How high the plants grow in the different soils.
Explanation:
The dependent variable is what happens as a result of what the experimenter changes.
The experimenter could measure how high the plants grow when placed in soil with different pH values.
Answer:
Liquid
Explanation:
Earth’s core is liquid because it’s hot enough to melt iron, but only in places where the pressure is low enough
