Suppose the mean salary for full professors in the united states is believed to be $61,650. a sample of 36 full professors revealed a mean salary of $69,800. assuming the standard deviation is $5,000, can it be concluded that the average salary has changed or is it still the same. (using a 0.05 level of significance)? (this mean you should perform a hypothesis testing h^0: μ_y^0=$61.650) ( provide 2 approached both the "t-test" and "p-value" approach. ) create the 95 % confidence interval for the population mean using the information above?

Suppose there is a simple index of three stocks, stock abc, stock xyz, and stock qrs. stock abc opens on day 1 with 4000 shares at $3.15 per share. stock xyz opens on day 1 with 5000 shares at $4.30 per share. stock qrs opens on day 1 with 6000 shares at $4.60 per share. the price of stock abc on day 8 begins at $3.50. the price of stock xyz on day 8 begins at $3.90. stock qrs opens on day 8 with a price of $4.50 per share. assume that each stock has the same number of shares that it opened with on day 1. what is the rate of change of this simple index over 1 week?

Astudent simplified a rational expression as shown.

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