What would be my manipulated and Controlled variable?

im doing a science fair project and i need help on what the manipulated variable and the controlled variable is.


this is the problem ::::





PROBLEM: What solvents will remove the permanent marker ink from glass better, water, alcohol, vinegar, or detergent?What would be my manipulated and Controlled variable?
manipulated variable





Definition


Condition or quantity altered (manipulated) to regulate, or initiate a change in, some other condition or quantity





controlled variable


Alternative term for independent variable.





independent variable


Definition


Factor or phenomenon that causes or influences another associated factor or phenomenon called dependent variable. For example, income is an independent variable because it causes and influences another variable consumption. In a mathematical equation or model, it is that variable whose value is given. In an experiment, it is the controlled condition (that is allowed to change in a systematic manner) whose effect on the behavior of a dependent variable is studied. Also called controlled variable, explanatory variable, or predictor variable.





PROBLEM: What solvents will remove the permanent marker ink from glass better, water, alcohol, vinegar, or detergent?





Answer.


Control variables ( my suggestions )


I might add no solvent and use that as the control(independent ) experiment.





Also cleaning material (cloth?) ,





pressure applied , (a Weight on cloth pushed with stick ?)





number of passes across mark (same for each ink line )





length and applied thickness of ink. ( Three pens per solution and use ruler? confirms if maybe a bad pen )





Drying time should be approximately equal ( make all lines at same time ?)





glass cleanliness and moister ( one large piece of glass, wear plastic gloves ,hand oil prints )





How the solutions are applied also need to be constant throwout experiments. (measure equal amounts ,soaking time before strokes also.)





glass Temperature equal across the pane








manipulated variables are the other solvents listed above.





detergent in solution ? or 100% liquid detergent in bottle might be easier.





I think that should be all.





It just looks like al lot :)