Solve the following problem"
Q: The percent of concentration of a drug in the bloodstream x hours after the drug is administered is given by the function: K(x) = 4x/(3x2+27)
a) On what time intervals is the concentration of the drug increasing?
b) On what intervals is it decreasing?
c) When is the drug most effective?
You must show all steps, the equation used to solve the problem, and explain the meaning of the answer in order to receive credit for the solution.