Hello there, and thank you for posting your question here on brainly.
Short answer: C. Product of 2 rational numbers = a rational number.
Why?
The numbers are both rational because squared is a result of a number multiplied by itself. Like (3^2 = 9). It turns out as a rational number because you're multiplying by two positive numbers, which always turns out as a rational number. (3^2 * 4^2 ==> 144) [3^2 = 9] [4^2 = 16]
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Hi,
You can walk 9.3 miles per hour.
<em>Hope this helps!</em>
Answer:
Where
and 
We are interested on this probability

And the best way to solve this problem is using the normal standard distribution and the z score given by:

If we apply this formula to our probability we got this:
And we can find this probability using the complement rule:

Step-by-step explanation:
Previous concepts
Normal distribution, is a "probability distribution that is symmetric about the mean, showing that data near the mean are more frequent in occurrence than data far from the mean".
The Z-score is "a numerical measurement used in statistics of a value's relationship to the mean (average) of a group of values, measured in terms of standard deviations from the mean".
Solution to the problem
Let X the random variable that represent the variable of interest of a population, and for this case we know the distribution for X is given by:
Where
and 
We are interested on this probability

And the best way to solve this problem is using the normal standard distribution and the z score given by:

If we apply this formula to our probability we got this:
And we can find this probability using the complement rule:

Answer:
e^2 -7 = x
Step-by-step explanation:
2=ln(x+7)
Raise each side to the base of e
e^2 = e^ln (x+7)
The e^ln cancel
e^2 = x+7
Subtract 7 from each side
e^2 -7 = x +7-7
e^2 -7 = x
Answer:
282.7 cm
Step-by-step explanation: One spin is one circumference. That's π(diameter)= 282.7