$4.$ Add up two $16-$bit two's complement numbers. Convert the source numbers to the binary system, perform binary addition, convert the result back to the hexadecimal system$\mathrm{.}0$x$9$DE$0=$XXXX XXXX XXXX XXXXBinary$+0$xFDB$7=$YYYY YYYY YYYY YYYYBinary$=-----------------------------------------------------$BinaryXXXX XXXX XXXX XXXX$=0$xZZZZYour answer should be formatted as: XXXX XXXX XXXX XXXX $=0$xZZZZPlease pay your attention to the formatting, be accurate with all the white spaces and etc.