Jim Cramer answers viewers' Twitter questions from the floor of the New York Stock Exchange. This week, he weighs in on Yahoo!, which he explains is a buy as he believes CEO Marissa Mayer and her team will deploy its cash correctly. While he's concerned about wine reserves given a recent California earthquake, Cramer says Constellation Brands CEO Rob Sands is a fantastic manager and he recommends buying the stock on any weakness. However, he advises against buying Ciena Corp., instead recommending Cisco for investors who want to be involved in that space. Make sure to tweet your questions @jimcramer every Monday using #CramerQ.