A city engineering department is planning improvements to 4 traffic intersections. All intersections are of equal importance. The chief engineer is asked to list the intersections in the order that the work will be carried out. Answer the following questions, rounding your answers to two decimal places where appropriate.

(a)How many different orderings are possible?

(b)A city tax-payer guesses at the order of the traffic improvements. What is the probability that this guess will turn out to be correct? Round off your answer to four decimal places.