Answer:
Step-by-step explanation:
9 * -9 * -1 =
-81 * -1 =
81 <===
In multiplying (or dividing), if the signs are the same, the result is positive
if the signs are different, the result is negative
these rules do not apply to addition or subtraction

The surface of interest can be parameterized by

with

and

.
The area of the surface

is given by the surface integral

We have

so the area is given by the double integral
According to the statement above, The Hamden board of education called every <span>tenth person on the registration list. So let's analyze each case:
</span><span>The sample is not randomly chosen (FALSE)
Given that the statement doesn't tell us anything about the way they choose the sample, it is reasonable to conclude that this is a </span>randomly chosen. They called every tenth person on the registration list until the number of people was 40.
The sample should be larger to give more reliable information (TRUE)
You did not have to use mathematics to determine that you would need more information to get a conclusion. You must increase the sample, that is, the sample must be larger to give a reliable information.
The sample size is too large to make inferences (False)
This is explained in the previous item. If the sample should be lager is because the size is not too large.
The sample size is too small to represent the population (TRUE
This is true because 40 voters represent barely 0.5% of the entire list. This list has 7300 voters, so getting the conclusion from this sample doesn't provide with a strong conclusion.
<span>The sample size is too small and will show larger variation. (FALSE)
Although the sample size is too small, the sample size not necessarily will show variation. In fact, it is possible that it does not show any variation and most of the people feel well about building a new media center for the middle school but it doesn't mean that the whole community does.
The sample is invalid because it randomly chooses voters. (FALSE)
It is false because in probability studies the sample is chosen randomly, so you get conclusions about the whole population always taking samples that represent the population as a whole.
The sample size is too small and can lead to false inferences (TRUE)
You can get false conclusions given that the sample size is too small. <span>It's important to note that the sample size supports the conclusion of the study, so the sample must increase to have a reliable study.
</span>
</span>
The answers to the question would be number 2, number 3, and number 5
Answer: 1.8 bags
Step-by-step explanation:
From the question, given that robby have 4 4/9 bags of pet food, 2/5 were dog food
2/5 of 4 4/9 = dog foods
Convert 4 4/9 to proper fraction= 40/9
2/5 of 40/9 means 2/5 × 40/9
= 16/9
= 1.78 or 1.8
I hope this helps, please mark as brainliest answer.