(a) The diagram below shows a simplified abacus. The beads are able to be moved down' or 'up' to represent any number that we wish to. For each of the numbers below, move the beads so that each diagram represents a number below: 263 (i) (ii) 754 1096 (iv) 34.85 (iv) 0.297 00:00 [10 marks] (b) What are the problems you encounter in answering part (a) above? [3 marks] (c) How did you overcome the problems in part (b)? [3 marks] (d) Do you think using the abacus for addition can be faster than using a calculator? Explain. [4 marks]