4. [15 marks] Integer Multiplication I. a) Multiply the following two 12-bit binary natural numbers. The multiplicand is 100110 111001 ([9b9]) and the multiplier is 11010 ([1a]). Show, all in hexadecimal, i) the initial value of the accumulator, and ii) each term added to the accumulator, and iii) the partial sum after each addition. The last addition yields the final value. b) Redo the multiplication steps exactly as in question 4 a), but initialize the accumulator to s = 11011 ([1b]) instead of 0. Show the same intermediate and final values. (This is called "fused multiply-add").