It's a little hard to see but it looks like A
hope that helps :)
This might look hard at first, but if you break it down into parts, it will be much easier. With that said, start with what you know. You see that the word problem says "the difference of y and 9", which means that you have to stubtract them. So, part of the equation is going to be y - 9. Now to look at the rest of the word problem. It says to divide by 3, so now you have to take what you have so far and divide that by 3. This means that you are going to have to divide the y - 9 by 3.
Your answer should be:
y - 9 / 3
***** Note: The slash means division. *************************************
Answer:
and 
Step-by-step explanation:
The null hypothesis
states that a population parameter (such as the mean, the standard deviation, and so on) is equal to a hypothesized value. We can write the null hypothesis in the form 
In this context, the investigator's null hypothesis should be that the average total weight is no different than the reported value by the FAA. We can write it in this form
.
The alternative hypothesis
states that a population parameter is smaller, greater, or different than the hypothesized value in the null hypothesis. We can write the alternative hypothesis in one of three forms

The investigator wants to know if the average weight of passengers flying on small planes exceeds the FAA guideline of the average total weight of 185 pounds. He should use
as his alternative hypothesis.
Answer:
What ratio, and give me more details and I will come back and edit my answer.
Step-by-step explanation:
Answer:
5km + 4.5km +2.7km = 12.3km