Answer with Explanation:
We are given that
Radius of solid core wire=r=2.28 mm=
Radius of each strand of thin wire=r'=0.456 mm=
Current density of each wire=
a.Area =
Where 
Using the formula
Cross section area of copper wire has solid core =
Current density =
Using the formula
Total number of strands=19
Area of strand wire=
b.Resistivity of copper wire=
Length of each wire =6.25 m
Resistance, R=
Using the formula
Resistance of solid core wire=
Resistance of strand wire=
<span> A. By ensuring that they never engage in risk behaviors
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You need to form a hypothesis based on what is already known about gold and then devise an experiment to test this hypothesis.
For example, the density of gold is well known. So your hypothesis would be that if the rock were gold, you could predict the amount of water displacement in a beaker simply by measuring the weight of the rock.
The steps would be:
1. research what is already known about your field of investigation (in this case <em>gold</em>).
2. Using that information, formulate a hypothesis that allows you to make predictions.
3. Devise an experiment that can test your predictions.
