Answer:
negative
Explanation:
When something slows down, its acceleration is the opposite of the velocity.
A controlled variable is the one that is kept constant, the manipulated variable is the independent variable in an experiment , it is called manipulated because is the one that can be changed. A responding variable or variables are the dependent variables that change as a result of the changes in the manipulated variable.
The answer is A. Mixtures can be separated by physical means
A pure substance cannot be separated.
