Complete Question
The complete question is shown on the first uploaded image
Answer:
a
Yes the researcher can conclude that the supplement has a significant effect on cognitive skill
b

c
The result of this hypothesis test shows that there is sufficient evidence to that the supplement had significant effect.The measure of effect size is large due to the large value of Cohen's d (0.5778 > 0.30 )
Step-by-step explanation:
From the question we are told that
The sample size is n=16
The sample mean is 
The standard deviation is 
The population mean is 
The level of significance is 
The null hypothesis is 
The alternative hypothesis is
Generally the test statistics is mathematically represented as

=> 
=> 
Generally the p-value is mathematically represented as


From the z-table

=> 
=> 
From the obtained values we see that 
Decision Rule
Reject the null hypothesis
Conclusion
There is sufficient evidence to conclude that the supplement has a significant effect on the cognitive skill of elderly adults
Generally the Cohen's d for this study is mathematically represented as

=> 
=> 
Answer:

Step-by-step explanation:
we know that
The area of the figure is equal to the area of rectangle plus the area of semicircle
step 1
Find the area of rectangle
The area of rectangle is equal to

where

substitute

step 2
Find the area of semicircle
The area of semicircle is equal to

we have
---> the radius is half the diameter

substitute


step 3
Find the area of the figure

Answer:
5545
Step-by-step explanation:
The answer is $29.99. First, you add $10 to $49.98 which equals 59.98. Next, set up a proportion: x over 59.98 equals 50 over 100. 59.98 times 50 equals 2,999. Now divide 2,999 by 100 and you get your answer.
Answer:
45
135
Step-by-step explanation:
x-y = 90
x = 3y
3y - y = 90
2y = 90
y = 45
x = 3×45 = 135