Answer:
The correct answer is - an observational study.
Step-by-step explanation:
It is given that, Researchers periodically survey a few thousand of the patients. These are taking specific medicine patients and researchers taking this survey to find the connection between that medication and the subjects' general health.
So, it can say that the researchers observed the patient's health by the effect of the medication, therefore, the Observational Study is the given method of gathering data.
Always foucus on the teacher ask help when needed
Answer:
What the first person said
B, because you can't get the square root of a negative number
Answer:
30 hours
Step-by-step explanation:
The equation we use is 1/15 + 1/x = 1/10. X being the amount of time it takes Ian alone. X works out to 30 hours which is the answer