1. A modi?ed NRZ code known as enhanced-NRZ (E-NRZ) operates on 7-bit words; invert- ing bits 2,3,6 and 7; and adding one parity bit to each word. The parity bit is chosen to make the total number of 1s in the 8-bit word an odd count. What are the advantages of E-NRZ over NRZ? Are there any disadvantages?