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 .
The correct answer to the question is 1.4
Answer: $9 per hour
Step-by-step explanation:
$36 divided by 4 hours of work = $9 per hour