I think the answer is C. 45 units
Answer:

Standard error of mean = 689
Step-by-step explanation:
We are given the following information in the question:
Mean, μ = $28,520
Standard Deviation, σ = $5600
Mean of sampling distribution =

As per Central Limit Theorem, if the sample size is large enough, then the sampling distribution of the sample means follow approximately a normal distribution.
Sample size, n = 66
Since the sample size is large, we can use normal distribution for approximation.
Standard error of mean =

12 is a factor of 36 and of course 12, so
Answer: 12
1/4(8x+56)=20
1/4(8x)+1/4(56)=20
2x+14=20
2x=20-14
2x=6
X=3
-0.24 should be the answer. idk i might be wrong. im not to great at math just i just used a calculator