The number of trades (in thousands) completed daily by an online stock brokerage follows a normal distribution with a mean of 108.2 and a standard deviation of 24.8. On average, the brokerage receives $7.87 commission per trade. For samples of size n=18=18 days:

1. Determine the mean and standard deviation of the sampling distribution of the sample mean daily commissions received (in thousand dollars) accurate to 3 decimal places: a) Mean = Correct thousand dollars b) Standard deviation = Correct thousand dollars
2. Determine the following probabilities (as percentages) accurate to one (1) decimal place.

What is the probability that the mean daily commissions received is

1. a) less than $785,426? %% b) between $777,556 and $955,418? %%
2. For the given sample size, what is the maximum average daily commissions receivable from the lowest 4% volume trading days?

Round to the nearest thousand dollars.