I believe Winter is <span>your answer.</span>
A) all mechanical waves need a medium to travel through.
This is true because mechanical waves move in a wave like manner at the atomic level. This is why an table vibrates when you put a speaker on top of it .
Answer:Trials are repetitions of the same procedure. These are done for a couple of reasons: To minimize the impacts of errors done in any one trial by averaging multiple trials together. To minimize random effects and the effects of uncontrolled variables by averaging multiple trials together.
Explanation:
The answer is false because receiving an electrical shock is not an example of a negative punishment if you forget to turn off the power.