Answer:
The independent variable is the condition that you change in an experiment. It is the variable you control.
Explanation:
It is called independent because its value does not depend on and is not affected by the state of any other variable in the experiment. Sometimes you may hear this variable called the "controlled variable" because it is the one that is changed.
The answer is E and F.
Hope this helps!!
Magnesium (Mg)
The reason for this is the reactivity of the listed metals. Gold and silver are extremely unreactive metals. It is because of this unreactive nature that they remain in good condition for long periods of time, and are preferred in jewelry. Copper, although more reactive than gold and silver, is still not reactive enough to react with HCl.
The only metal that will react is magnesium.