$[$Financial Ratios$]$ Use the financial statement data for the Bike$-$With$-$Us Corporation provided in Problem $3$ to make the following calculations:

A$.$Calculate the operating return on assets.

B$.$ Determine the effective interest rate paid on the long$-$term debt.

C$.$ Calculate the NOPAT margin. How does this compare with the results for the net profit margin? Did the owners benefit from the use of interest$-$bearing long$-$term debt?