Answer:
dr/dR= s/(s-r)
b) taking all values positive.. the answer is INCREASING
Step-by-step explanation:
a) R= r*s/(s+r)...
making r subject of formulae ... r = R*s/(s-r)
diff of (r) wrt R= s/(s-r)...
b) from the eqt R=r*s/(s-r)
and increase in r would always lead to an increase in R.. due to the multiplication power of the numerator. also with the condition that all values are positive..