Answer:
Step-by-step explanation:
sin = opposite / hypotenuse
ED is the opposite leg to angle C
CD is hypotenuse as opposite to angle E
<u>Substitute values</u>
Answer: D). This was a cross-sectional cohort study
Step-by-step explanation:
The given situation is an example of cross sectional cohort study because the investigator choose the samples from the population using cross sectional method and use the same sample source for analyzing the independent variables for specific period of time or intervals of time to assess the history of exposures and outcomes.
Here, the lung function is tested at an interval of 7 years compared with the levels of exposure to the coal ash so it is the example of cross sectional cohort study.
The confidence interval for the mean usage of water is (18.7,20.5).
Given population standard deviation of 2.4, mean of 19.5 gallons per day and confidence interval of 98%.
We have to find the confidence interval for the mean usage of water.
To find out the confidence interval we have to first find margin of error.
μ=19.5
σ=2.4
α=0.98
α/2=0.49
We have to find the z value for the p value 0.49 which is z=2.33
Margin of error=z*μ/
=2.33*19.5/
=0.82
lower level=mean -m
=19.5-0.82
=18.68
after rounding upto 1 decimal
=18.7
upper mean = mean+m
=19.5+0.82
=20.52
Hence the confidence interval for the usage of water is (18.7,20.52).
Learn more about margin of error at brainly.com/question/10218601
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Answer:
(x+4)(2x+1)
Step-by-step explanation:
1. 2x^2+8x+x+4 ----- split the second term in 2x^2 + 9x+4 into two terms.
2. 2x(x+4)+(x+4) ----- Factor out common terms in the first two terms, then in the last two terms.
3.(x+4)(2x+1) ------ factor out the common term x+4