(ii) Find the single matrix that represents the network obtained by combining the network in part (a) (i) with the network above; that is, the combined network that represents the number of children from districts A and B who do keep-fit classes and the number of children from districts A and B who do team sports. (You are not asked to draw this network). [2] (iii) Find the number of children who do keep-fit classes and the number of children who do team sports out of the 240 children from district A and the 200 children from district B. ] Question 3 - 5 marks You should be able to answer this question after studying Unit 9. You should use Marima to answer this question. Include a printout or screenshot of your Marima worksheet with your solution. Your solution should include a clear statement of the problem and the method used. Remember that for good mathematical communication you should present your answer clearly. Three equine stables each keep three types of horse over the winter: ponies, hacks (horses used for general-purpose riding), and racehorses. Ash Hill Stables keeps 4 ponies, 9 hacks and 7 racehorses; Birch Wood Stables keeps 2 ponies, 14 hacks and 16 racehorses; and Cherry Tree Stables keeps 12 ponies, 6 hacks and 4 racehorses. On a typical winter's day, the horses in Ash Hill Stables eat 394 1b of hay, the horses in Birch Wood Stables eat 656 lb of hay, and the horses in Cherry Tree Stables eat 380 lb of hay. By modelling the problem as a system of three linear simultaneous equations, use matrices to find the amount of hay (in lbs) a pony, a hack and a racehorse each eat on a typical winter's day. [5] Question 4 - 10 marks You should be able to answer this question after studying Unit 10. (a) For the infinite geometric sequence (In) whose first four terms are 3.2, 6.72, 14.112, 29.6352, find the values of the first term a and the common ratio r, and write down a recurrence system for this sequence. [4) (b) Write down a closed form for this sequence. [2]