Answer:
d.
Step-by-step explanation:
Hello!
The objective of this test is to know if aerobic exercise modifies hippocampus activity. A random sample of 120 elderly men and women was taken and divided into two groups.
Group 1: Walked around a track three times a week.
Group 2: Did a variety of less aerobic exercises, including yoga and resistance training with bands.
After a year their brains were scanned showing that group 1 had an increase of 2% in their hippocampus and group 2 showed a decrease of 1.4%
a. True, this type of observational study can be the prelude to a more formal statistical study.
b. True, the explanatory variable is "type of exercise", it's the variable that the investigator suspects influence the hippocampus volume.
c. True, the objective of this experiment is to test if there is any modification on hippocampus volume, that's why the volume of the hippocampus was measured, before and after a year of exercise.
d. False, this is an observational study, you cannot establish a causal relationship between the two variables. Just inform you that there seems to be an association. To be able to generalize the results to all elderly population you need a more formal statistical experiment to support your conclusions.
I hope it helps!
Answer:
Half of the total cost was paid when her braces were put on. The total cost is $3,200. How much will Kelly's parents need to save each month to pay off the ..
Step-by-step explanation:
Answer:
The Area of Δ ABC = 219.13
Step-by-step explanation:
<em>The hard part about this problem is finding the area without the height</em>
The formula to do this is Area = 
A, B, C represent the sides
S represents 
(A + B + C)
In this equation, we will make the base be A, and the other two sides will be B and C
<u>Sides B and C are the same length</u> because they meet at a 90° angle
Lets plug the numbers into the variables
A = 28
B= 21
C= 21
<u>Remember:</u> S represents (A + B + C)
S = (28 + 21 + 21)
S = (70)
S = 35
<em>Lets plug the numbers into the Area Formula now!</em>
Area = 
According to the order of operations, we need to do the calculations in parentheses <u>first</u>
35 - 28 = 7
35 - 21 = 14
35 - 21 = 14
14 x 14 x 7 = 1372
1372 x 35 = 48020
= 219.13
The Area of Δ ABC = 219.13
Answer:
V≈904.78
Step-by-step explanation:
