* Bomb hits second-hand bike market in Shi'ite neighbourhood
* Other violence elsewhere kills at least 11
By Kareem Raheem
BAGHDAD, Feb 27 (Reuters) - At least 42 people were killed Wednesday as a motorcycle rigged with explosives detonated in Baghdad's Sadr City and militants targeted mostly Shi'ite neighbourhoods around the country.
The motorcycle was parked in a second-hand market in...