A House Agriculture subcommittee looked at provisions in the new financial regulations law governing speculation in metals, energy and agricultural commodities.  The law requires the Commodity Futures Exchange Commission to devise rules for position limits, which are essentially restrictions on the number of bets traders can make on a certain commodity.  Witnesses include CFTC chairman Gary Gensler, as well as one of the CFTC commissioners. Also appearing were commodities brokers and representatives of trade groups.