Answer:
11.5
The sample standard deviation measures the spread of a data distribution of the sample. It is usually used to estimate the population standard deviation
Data:
Formula: diameter = 2*radius
Formula: (<span>Circle length)
</span>

<span>
Solving: </span><span>Using the data
</span>diameter = 2*radius
20 = 2*r
2r = 20


<span>Now, replace in the circumference length formula
</span>



Answer:
<span>
The exact circumference of the circle is </span>
For this case we have the following equation:

Where,
w: The weight of a spring in pounds
E: the energy stored by the spring in joules.
Substituting values we have:

Making the corresponding calculation:
Answer:
the approximate weight of the spring in pounds is: