B: Signed Hexadecimal Subtraction (Based on section 3.2 in the text) Calculate the following values by hand. All numbers represent signed 16-bit hexadecimal numbers stored in sign-magnitude format. Make sure you show your work, including all borrows or intermediate steps. The result should be written in hexadecimal. Place your answer in the box. ) a) b) 5 E D 4 07 A4 A 8 1 F - 5 D 2 E 2