SACRAMENTO, Calif. — A mother demanded answers Monday after she says her 11-year-old son was chased, tackled and bloodied by California State Fair officers during the fair’s Kids Day. The incident on Tuesday, July 19, brings up fresh allegations of racism and excessive force from officers. Elk Grove’s Cynthia Martin said at a news conference just outside the Cal Expo gates Monday her son was horsing around with friends outside of a State Fair roller coaster. That horseplay led fair police to chase down and injure the 11-year-old before questioning him for more than 30 minutes and forcing him t…