7. Show the result of each of the following calculations in binary using the two's complement method Assume 9 BITS. a. 63-36 b. -91-27 8. In a certain digital system, the decimal numbers from 000 through 999 are represented in BCD code. An odd-parity bit is also included at the end of each code group. Examine each of the codes below, and assume that each one has just been transferred from one location to another. Some of the group contains errors. Assume that no MORE THAN TWO errors have occurred for each group. Determine which of the code groups have a single error and which of them DEFINITELY have a double error. (Hint: Remember that this is a BCD code). a. 1001010110000 + Parity bit b. 010001110110 0 c. 0111110000011 d. 1000011000101