Answer:
C) Re-do the measurements, several times, and take the average density before making a decision.
Explanation:
For the correct identification of the metal, weather its nickel or copper, Carl should repeat the experiment several times and take the average density before making the decision. It is important because it reduces the chance of error and ensure the data integrity. The more the sample size is, lessen would be the error.
Because the use of more can get us more items that can grow the population and intrest.
The benefits are that you don't have to rely on limited resources and you won't be contribution to global warming but the drawbacks are that you have to find a way to make it run by itself and deal with it not working sometimes.
Vertical stairs :P: W = (20 N) * (6.0 m) * cos (0 degrees) = <span>120 Joules
At 45 degrees: W = (20.0 N) * (6.0 m) * cos (45 degrees) =
(20N) * 6m) * (</span><span>0.707106781) = 84.853 Joules</span>