You are provided with the following table about a retail business $($in $$)$:

$\backslash$table$[[,2021,2022],[$Net sales,$12,800,14,000],[$Cost of goods sold,$8,320,9,520],[$Gross profit, $),()],[$Expenses$,1,280,1,680],[$Net profit,$()(),]]$

Inventory $($ending balance $1,720$ in $2020)$ Ending balance $1,880$ Ending balance $2,120$

Required:

$(1)$ Calculate the four indicators, "gross profit ratio", "profit margin", $"($operating$)$ expenses to sales ratio", and "inventory turnover" for year $2021$ and year $2022.$

$(2)$ Comment on the profitability aspect of the business.