0.8 recurring (that is, 0.88888...) is already expressed as a decimal. Expressed as a proper fraction, this is equal to 8/9 or eight ninths.
8.61111 repeating
Either, the decimal with a line over what's repeating (eg. 0.6 with a line over it), or decimal repeating (eg. "point six repeating").
0.6666 repeating
0.4444 repeating
Eight and five elevenths as a decimal is 8.4545 (repeating).
0.6666 repeating
.66 repeating
Yes, it can.
0.8484 repeating
1.142657 repeating
2.6666 repeating
0.7272 repeating