Sorry this got to you super late. At least others looking for the answer can find it.
2 miles: 1/2 hour
? mile: 1 hour
(2÷1/2)mi/h or B is your final answer. Hope it help!
Answer:
a)
b) 
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".
Part a
Let X the random variable that represent the weights 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 like this:
And in order to find these probabilities we can find tables for the normal standard distribution, excel or a calculator.
Part b
For this case we select a sample size of n =32. Since the distribution for X is normal then the distribution for the sample mean
is given by:
And the new z score would be:



Because December is really cold
Answer:
$361,223
Step-by-step explanation:
Each year, the value is multiplied by 1+5% = 1.05. After 51 years, it has been multiplied by that factor 51 times, so is now ...
$30,000×1.05^51 ≈ $361,223