Muhammad Harby fasts from sunrise to sunset during the holy month of Ramadan. Then, after he breaks his fast, he heads from Brooklyn to Midtown Manhattan every day for a late night appointment with hundreds of homeless New Yorkers who rely on him and other Muslim volunteers for a hot meal. They pass out chicken and rice, vegetables and fresh fruit from a food truck run by Muslims Giving Back, a charity based in Sunset Park, Brooklyn, whose activities -- and coffers -- swell during Ramadan, when Islamic teachings urge Muslims to donate to charity and do good works for the neediest around them.