Answer:
Advantages:
- It is easier for people to choose an option rather than to write an essay. The questionnaire reflects what the person is thinking and what the person's point of view is, which as a result makes it easier to analyze and conclude results
- A wide range of questions can be asked within one questionnaire, which makes it an effective way to conduct a survey/test
Disadvantages:
- A person has to read carefully in order to answer each question and sometimes there is lack of concentration by the person filling in the questionnaire
- It is slightly difficult to write an effective questionnaire, that would able to test a vast knowledge/ conduct a survey so that an effective analysis can be done
Step-by-step explanation:
Answer:
12P3 = 1320
Step-by-step explanation:
How you need select three persons of a group of twelve persons, but in the selection each member of the group has a different position, then you need use a permutation
Permutation is defined how

In our case n = 12 and r = 3
Thus

12P3 = 1320
Answer:
d. The interval contains only negative numbers. We cannot say at the required confidence level that one region is more interesting than the other.
Step-by-step explanation:
Hello!
You have the data of the chemical measurements in two independent regions. The chemical concentration in both regions has a Gaussian distribution.
Be X₁: Chemical measurement in region 1 (ppm)
Sample 1
n= 12
981 726 686 496 657 627 815 504 950 605 570 520
μ₁= 678
σ₁= 164
Sample mean X[bar]₁= 678.08
X₂: Chemical measurement in region 2 (ppm)
Sample 2
n₂= 16
1024 830 526 502 539 373 888 685 868 1093 1132 792 1081 722 1092 844
μ₂= 812
σ₂= 239
Sample mean X[bar]₂= 811.94
Using the information of both samples you have to determina a 90% CI for μ₁ - μ₂.
Since both populations are normal and the population variances are known, you can use a pooled standard normal to estimate the difference between the two population means.
[(X[bar]₁-X[bar]₂)±
*
]

[(678.08-811.94)±1.648*
]
[-259.49;-8.23]ppm
Both bonds of the interval are negative, this means that with a 90% confidence level the difference between the population means of the chemical measurements of region 1 and region 2 may be included in the calculated interval.
You cannot be sure without doing a hypothesis test but it may seem that the chemical measurements in region 1 are lower than the chemical measurements in region 2.
I hope it helps!
Most likely true. It depends. When the distribution is skewed with an extreme tilting it to one side, median would be a better measure of central tendency. If the extremities are almost balanced on both sides then mean would be a better measure of central tendency.
Answer:
c = 4
Step-by-step explanation:
In a perfect square trinomial, the following relationship is true:

In order for the given expression to be a perfect square trinomial:

Solving for 'c':

Therefore, c must be equal to 4.