12. Nadia's ofce is four blocks east and three blocks south of her house. Assume that she walks onlj-..r east or south when going from home to work. a} Use Pascal's method to determine how many different routes Nadia can take. (3 marks. T] b} Use a permutation calculation to determine how man}...r different routes Nadia can take. (2 marks+ T} o) If her colleague lives 2 blocks east and 1 block south from her house+ howl-lI many routs can she take to work+ if she picks up her colleague on the way? {3 marks. T] d} Brieyr discuss the advantages and disadvantages of these two methods for counting paths. (2 marks+ A.)