4πr2
= 4×π×42
= 64π
= 201.06192982975 inches2
The answer should be the last one
Answer:
I think E.
Step-by-step explanation:
The surveyor selects the twentieth student who enters the building. The student do not enter the building to be surveyed but for other reasons and the researcher take advantage of that and selects them. This is a form of continence sampling.
The researcher selects every twentieth student and not any other. Therefore, the sampling is systematic in nature.
Finally, students selected to participate in the survey are free to choose if to participate in he survey or not. Therefore, it is voluntary kind of sampling.
Therefore, the applicable sampling methods are convenience, systematic, and voluntary.
The grade on the west side would be the vertical rise divided by the horizontal run or 525 divided by 800' or rounded off to 66% (a steep grade as in an underground mine a grade of 25% is considered very steep for vehicles to go up or conveyors to travel). On the east side the 40% grade was obtained by dividing the 525' vertical height by the 1300' run.
