Answer
$a-E(0110)=000111111000\,\,,D(111111000111)=1101 \\
b-E(1010)=111000111000\,\,,D(000000111111)=0011
$
Work Step by Step
$E(s) =\,the\,string\,obtained\,from\,\,s\,\,by\,replacing\,each\,\\
bit\,of\,\,\,s\,\,\,by\,the\,same\,bit\,written\,three\,times.\\
D(t) = the\,string\,obtained\,from\,t\,by\,replacing\,each\,consecutive\,\\
triple\,of\,three\,identical\,bits\,of\,\,\,t\,\,by\,a\,single\,copy\,of\,that\,bit.\\
a-E(0110)=000111111000\,\,,D(111111000111)=1101 \\
b-E(1010)=111000111000\,\,,D(000000111111)=0011
$
