Vernon Corporation's balance sheet indicates that the company has $$670,000$ invested in operating assets. During Year $2,$ Vernon earned operating income of $$89,780$ on $$1,340,000$ of sales.

Required

a$.$ Compute Vernon's profit margin for Year $2.$

b$.$ Compute Vernon's turnover for Year $2.$

c$.$ Compute Vernon's return on investment for Year $2.$

d$.$ Recompute Vernon's ROI under each of the following independent assumptions:

$(1)$ Sales increase from $$1,340,000$ to $$1,608,000,$ thereby resulting in an increase in operating income from $$89,780$ to $$104,520.$

$(2)$ Sales remain constant, but Vernon reduces expenses, resulting in an increase in operating income from $$89,780$ to $$92,460.$

$(3)$ Vernon is able to reduce its invested capital from $$670,000$ to $$536,000$ without affecting operating income