Answer:
2
Step-by-step explanation:
The reciprocal of a number n is 
Here n = 0.5, then reciprocal is
= 2
For this case we have by definition, that the volume of a cone is given by:

Where:
A: It is the cone radius
h: It's the height
They tell us that the diameter is 21 m, then the radius is half the diameter, that is: 10.5m. The height is 4m. Substituting the data:
.
Finally, the volume of the cube is
ANswer:
Option B
Answer:


And the best option would be:
D. (0.191 to 0.249)
Step-by-step explanation:
For this case we know that the mean is:

And the standard error is given by:

We want to construct a 68% confidence interval so then the significance level would be :
and
. The confidence interval is given by:

Now we can find the critical value using the normal standard distribution and we got looking for a quantile who accumulate 0.16 of the area on each tail and we got:

And replacing we got:


And the best option would be:
D. (0.191 to 0.249)
I think k equals negative 2, or -2.<span>
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