If a company spends million dollars on research, it sales will be s million dollars, where r and s are related by s = 3 55.(a) Find ds/dr by implicit differentiation and evaluate it at r = 4, s = 3. [Hint: Differentiate the equation with respect to r.]ds/dr=(b) Find dr/ds by implicit differentiation and evaluate it at r = 4, s = 3. [Hint: Differentiate the original equation with respect to s.]dr/ds=(c) Interpret your answer to part (a) as a rate of change.Given ds/dr = n, this means that the rate of change of sales with respect to research expenditures is n, so that increasing research by one million dollars will increase sales byabout n million dollars (at these levels of r and s). Given ds/dr = n, this means that the rate of change of research expenditures with respect to sales is n, so that increasing sales by one million dollars will increase research byabout n million dollars (at these levels r and s).Changing research will not affect sales.Interpret your answer to part (b) as a rate of change.Changing sales will not affect resGiven dr/ds=m, this means that the rate of change of sales with respect to research expenditures is n, so that increasing research by one million dollars will increase sales byabout m million dollars (at these levels of r and s).Given dr/ds=m, this means that the rate of change of research expenditures with respect to sales is m, so that increasing sales by one million dollars will increase researchby about m million dollars (at these levels of r and s).