Answer:
This is an observational study based on a stratified sample.
Step-by-step explanation:
This study aimed to check which clean-up/drying up method after handwashing was more effective; that is, do dryers eliminate more germs than paper towels.
It involved 100 people that took part in the study. The 100 of them contaminated their hands and were instructed to wash their hands with soap and water for 15 seconds before the participants are randomly grouped into two strata; one stratum/group (consisting of 50 participants) that dries their hands with a dryer and another (also consisting of 50 participants) that dry their hands with paper towels.
An observational study is one in which data is collected only by monitoring the events of the study. The conductor of the study in no way tries to intervene or control any of the variables being studied. No control, no tweaking of factors, just observe and record data.
An observational study based on a stratified sample is an observational study that uses the stratified sampling method to carry out its objectives. It randomly puts each of the participants being observed into groups or strata. Each group of randomly assigned participants are then required to run the test for one of the variables being compared.
This is exactly what the study in the question describes. This is why this study is undoubtedly an observational study based on a stratified sample.
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Answer:
Both
Claire
Andre
Neither
Step-by-step explanation:
We have to determine whether each point lies on Claire's line (blue) and whether it lies on Andre's line (black).
Point A is the intersection of both lines, hence the statement represents them both.
Point B only lies on Claire's line.
Point C is the start of Andre's line.
Point D is outside of both lines.
Answer:
biologists have a 14ft john boat with trolling motor for sale or trade for hipnopotomus
The first step is to find the CHANGE. This is done by subtracting the two values and taking the absolute value. Next step is to find the ratio of the change to the original and multiplying by 100% to make it a percentage.
So;
a) change = Ι60 - 25Ι = 35.
ratio of change to original = 35:25,
multiplying by 100% will give 35/25 × 100% = 140%.
Hence it is a 140% INCREASE.
b) change = | 30 - 66 | = 36
the ratio is 36:66
multiplying by 100% = 36/66 × 100% = 0.545454... ×100% ≈ 54.5%
Hence it is a 54.5% DECREASE.
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Answer:
What is this my head is paining
