Answer:
B. The observational study is a cross-sectional study because information is collected at a specific point in time.
Step-by-step explanation:
1) There are three types of Observational Studies: Case-control, cross-sectional and Cohort.
2) Since the researchers collected information from those 1800 adults at a certain time, then we can call it a cross-sectional study. It does not provide solid results since the research was not done over a period to collect further information. We don't know, for example, much more than what that association deeply mean.
3) If we wonder more, then the researchers would have to track those adults over a given period, i.e. a Cohort would be necessary.
4) Moreover, it's not "retrospective" for virtually every question, always makes us look back somehow, and it does not categorize a kind of observational study.
Answer:
3
Step-by-step explanation:
3 (1.5 - 0.5) = 3 (1) = 3 * 1 = 3. The value of the expression is 3.
Tell me if I'm wrong :)
Answer:
The number that goes in place of the question mark is 2.
Step-by-step explanation:
Let's solve it!
3x² + 12x - 24 = 0
First we can factor 3 out of each term:
x² + 4x - 8 = 0
Now we'll add 12 to both sides to complete the square:
x² + 4x + 4 = 12
And finish it off:
(x + 2)² = 12
So the answer to the question is 2
Bonus:
We can also now solve this for x:
(x + 2)² = 12
x = √12 - 2
x = 2√3 - 2
x ≈ 2 × ±1.732 - 2
x ≈ 1.464, -5.464
You would find the average of the probability for roses and daisies, which would be .98 + .94 = 1.92. Divide this by 2 to get .96. The probability of the bouquet having roses or daisies is .96.
