Answer: 176.
Explanation:
Formula to find the sample size is given by :-

, where
= Population standard deviation from prior study.
E = margin of error.
z* = Critical value.
As per given , we have
E= $100,000
We take 95% confidence interval.
Critical value (Two tailed)=

The required sample size =

[Round to next integer]
Hence, the required sample size = 176.