How many drops of caffeine she drops on the worm is the manipulated variable.
In an experiment, the independent variable is a manipulated variable. Due to the fact that you may alter it, it is termed the "manipulated" one. In other words, you can choose in advance whether to raise it or lower it. Only one variable should be changed at a time throughout an experiment.
The Independent variable is Caffeine's impact. the production and use of nitrogen fertilizers, as well as the burning of fossil fuels in autos, power plants, and industries, are dependent variables that are local in scope. the heart rate of the worm is the responding variable in this experiment.
When an earthworm is given a stimulant like caffeine, its heart rate rises. Does coffee make an earthworm's heart beat faster? is the research topic upon which the experiment is based. The effect of coffee is the independent variable in this research question, and the response it causes is a change in heart rate (the dependent variable) This brings us to the following theory: "If an earthworm is given a stimulant like caffeine, then its heart rate accelerates."
To know more about manipulated variable refer to: brainly.com/question/11505552
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I believe it’s B? I just dug out my old cell theory stuff lol that’s what Im gathering from it
The sun! It's solar radiation heats our planet, gives us light, and sustains life.
Explanation:
Methods to increase or reduce friction
Grease is added between the moving parts in machines, to reduce friction. Another method of reducing friction is by using bearings. When ball bearings are introduced between two surfaces friction is reduced because of the freely rotating metal balls.
I couldnt get it all into text for for some reason sorry, it said there were inappropriate words for some reason? but here you go :D sorry it took a while and didnt answer the last few