Perform the following additions. The corresponding $16-$bit binary numbers are in $2\text{'}$s complement notation. Provide your answers in hexadecimal.

a$.x025B+x26DE$

b$.x7D96+xF0A0$

c$.xA397+xA35D$

d$.x7D96+x7412$

$e.$ What else can you say about the answers to parts $c$ and $d?$