please answer all parts

A survey was conducted regarding investment portfolios, see Table below. Portfolio Sample Size Number of Online Traders Under $1,000,000 200 125 At least $1,000,000 150 75 a. Compute the sample proportions and verify the nonskewness criterion. [0.5 marks) b. Construct a 95% confidence interval for the difference in population proportions of online investors. [1.5 marks) c. Using the confidence interval in part (b), is there any evidence to suggest that the population proportion of online investors is different for these two portfolio classifications? 10.5 marks]