Answer: 0.6812
Step-by-step explanation:
Let p be the population proportion of trees are infested by a bark beetle.
As per given: p= 12%= 0.12
Sample size : n= 1000
Number of trees affected in sample = 1000
Sample proportion of trees are infested by a bark beetle. = 
Now, the z-test statistic : 
So, 

Hence, the value of the z-test statistic = 0.6812 .
(4-3n-5n2)
+( -2+n-3n2)
____________________
-2-2n-8n2
Answer:
Reject the null hypothesis.
Step-by-step explanation:
n1 = 16
n2 = 21
S.V1 = 5.8
S.V2 = 2.4
= 0.05
= Population Variance 1 ≤ Population Variance 2
= Population Variance 1 > Population Variance 2
Test statistic value = 5.8 / 2.4 = 2.417
Degrees of freedom is n - 1
15 and 20
Critical value is
= 2.2
2.417 > 2.2
we reject the null hypothesis as the critical value is greater than the test statistic.
We are trying to find miles/hour, which shows that we are going to be dividing the total number of miles by the total number of hours. Thus, in this case, the miles/hour rate will be:

He drove 40 miles in one hour.
Answer:
4/6 or 2/3...............