I believe it is D, stratified random sampling.
Hope this helps!!
Answer:
.05
Step-by-step explanation:
you divide 5 by 100 which makes it .05
Answer:
(25.732,30.868)
Step-by-step explanation:
Given that in a random sample of 42 people, the mean body mass index (BMI) was 28.3 and the standard deviation was 6.09.
Since only sample std deviation is known we can use only t distribution
Std error = 

t critical for 99% two tailed 
Margin of error
Confidence interval lower bound = 
Upper bound = 
The interest is compounded quarterly because the formula is
A=p (1+r/k)^kt
A it's 18810.67 but I will assume it's unknown ?
P present value 7350
R interest rate 0.045
K compounded quarterly 4
Now solve the formula as the interest is compoundedquarterly
A=7,350×(1+0.045÷4)^(4×21)
A=18,810.67
So the answer is quarterly